Elsevier Logo




Learn more about Elsevier's Drug Information today! Get the drug data and decision support you need, including TRUE Daily Updates™ including every day including weekends and holidays.




  • The insulins are primarily used in the treatment of patients with Type 1 or Type 2 diabetes mellitus.
  • Treatment goals include achieving appropriate glycemic control, reducing the development and progression of microvascular complications, and enhancing quality and quantity of life.
  • The insulins are a heterogeneous class of drugs, differing primarily in their onset of action, time to peak effect, and duration of action; the insulin analogs more closely mimic endogenous insulin secretion after meals (rapid-acting analogs) and basal insulin secretion (long-acting analogs) as compared to regular insulin and NPH insulin.
  • The use of insulin is associated with hypoglycemia and weight gain.
  • Compared to regular insulin and NPH insulin, the insulin analogs are associated with improved glycemic control and reduced hypoglycemia.

Pharmacology/Mechanism of Action

The exogenously administered insulins exert their primary effect of lowering blood glucose levels via the promotion of glucose uptake into peripheral skeletal muscle and adipose tissue, the inhibition of glycogenolysis (the hydrolysis of glycogen to glucose), and the inhibition of gluconeogenesis (hepatic glucose production). Insulin also regulates fat metabolism by enhancing the storage of fat (lipogenesis) and inhibiting the mobilization of fat for energy in adipose tissues (lipolysis and free fatty acid oxidation). In addition, insulin regulates protein metabolism (through increasing protein synthesis and inhibiting proteolysis in muscle tissue). Biosynthetic insulins are used as replacement therapy in patients with Type 1 and Type 2 diabetes mellitus (DM) to restore their ability to properly metabolize carbohydrates, fats, and proteins. Insulin administration also facilitates the replenishment of liver glycogen stores.


The time course of action of the various insulins and insulin analogs may vary considerably in different individuals or even within the same individual. The characteristics of activity (time of onset, time to peak, and duration) are listed in the tables as general guidelines. The rate of insulin absorption, and consequently the onset of activity are known to be affected by the site of injection, exercise, and several other variables.


Characteristics of Rapid Acting and Short Acting Insulins[22299][62395][62517][51227][62674][30510][54173][57572][63144]


Mean Onset



Special Notes

Insulin aspart* (rapid)

Novolog: 15 minutes (range 10 to 20 minutes)

Fiasp: 10 minutes

Novolog: 40 to 50 minutes

Fiasp: 91 to 133 minutes

Novolog: 3 to 5 hours

Fiasp: less than Novolog

Administered around meals for rapid acting products; 30 to 60 minutes before meals for regular insulin; covers insulin needs for meals


Rapid acting insulins mimic endogenous insulin secretion after meals in non-diabetic patients


Subcutaneous absorption of rapid acting insulins is less variable than regular insulin


Regular insulin is available in 2 concentrations; ONLY regular insulin 100 units/mL may be administered intravenously.

Insulin glulisine* (rapid)

20 minutes

60 minutes

3 to 5 hours

Insulin lispro (rapid)

15 to 30 minutes

30 to 90 minutes

3 to 5 hours

Regular insulin* U-100 (short)

30 minutes (range 10 to 75 minutes)

1.5 and 3.5 hours

8 hours (mean 5 to 7 hours)

Insulin, inhaled (Human Recombinant) (rapid)

12 minutes

35 to 55 minutes

2.5 to 3 hours

*Data available to support IV administration in selected clinical situations


Characteristics of Intermediate and Long-Acting Insulins[54477][50277][44086][65982][60453][58899][60172][60488]





Special Notes

Isophane insulin (NPH) (intermediate)

1.5 hours

4 to 12 hours

24 hours

Unwanted peaks of NPH insulin may lead to hypoglycemia; long acting insulins have decreased variability in patient response than NPH and decreased hypoglycemia


Insulin glargine and Insulin degludec provide basal coverage for 24 hours with a relatively constant concentration/time profile; other longer-acting insulins administered 1 to 2 times/day


Concentrated regular human insulin (500 units/mL) has different pharmacokinetic from lower concentrations of regular insulin, including a slower peak and longer duration of action

Insulin detemir (long)

1 to 2 hours

6 to 8 hours

24 hours

Insulin glargine U-100 (long)

1.5 hours

No peak

24 hours

Insulin glargine U-300 (long)

6 hours

No peak

36 hours

Insulin degludec (long)

1 hour

12 hours

At least 42 hours

Human Regular Insulin U-500 (intermediate)

30 minutes

4 to 8 hours

13 to 24 hours (mean 21 hours)


Characteristics of Pre-Mixed Insulins[40554][51122][51123]





Special Notes

Insulin aspart (30%), insulin aspart protamine (70%)

10 to 20 minutes

1 to 4 hours

Up to 24 hours

Advantages include a decreased number of injections and mixing elimination


Fixed ratios may not meet all glycemic reduction needs


2/3 of the daily insulin dose is given before breakfast and the remaining 1/3 is given before the evening meal

Insulin lispro (25%), insulin lispro protamine (75%)


Insulin lispro (50%), insulin lispro protamine (50%)

15 to 30 minutes

0.8 to 6.5 hours (mean 2.3 to 2.6 hours)

12 to 24 hours

Regular insulin (30%), NPH (70%)


Regular insulin (50%), NPH (50%)

30 to 60 minutes

1 to 5 hours

12 to 24 hours

Insulin degludec (70%), insulin aspart (30%)

14 minutes

2.3 hours

more than 42 hours

Administer once or twice daily with any main meal; give rapid or short-acting insulin at other meals if needed

Therapeutic Use

  • Dosage requirements are variable, ranging from 0.4 to 1 units/kg/day. Initial therapy can be less aggressive in type 2 DM than for type 1 DM. For type 1 DM, general insulin requirements range from 0.4 to 1 units/kg/day; most patients will require at least 3 administrations of insulin daily to achieve glycemic control.[60607] For type 2 DM, the average initial dose range is 0.2 to 0.6 units/kg/day. When used in combination with oral hypoglycemic agents, many patients with type 2 DM can be initially controlled on a single administration of a longer-acting insulin at a dosage of 10 units per day or 0.1 to 0.2 units/kg/day. However, most patients with type 2 DM will eventually require multiple administrations and total daily doses of 1 unit/kg/day or higher.[60607]
  • The ultimate goal of treatment in adults is to attain and maintain glycemic control (A1C less than 6.5 to 7, pre-prandial glucose 80 to 130 mg/dL, post-prandial glucose less than 180 mg/dL), improve clinical outcomes (particularly microvascular and macrovascular complications), and reduce mortality.[50185][50186][50187][50188][50189][34541][50190][50191][50321][60607][60608]
  • In the treatment on type 1 diabetes, insulin therapy may be initiated with a basal-bolus regimen and then further individualized to achieve treatment goals. In the treatment on type 2 diabetes, insulin is generally reserved for patients who continue to have an A1C above target despite dual/triple therapy with metformin and other antidiabetic agents. GLP-1 receptor agonists (GLP-1 RA) are generally the preferred choice to insulin in type 2 DM. Evidence from trials comparing GLP-1 RAs and insulin (basal, premixed, or basal-bolus) shows similar or even better efficacy in A1C reduction; GLP-1 RAs have a lower risk of hypoglycemia and are associated with reductions in body weight compared to weight gain with insulin. In patients who cannot tolerate a GLP-1 RA, or who fail to meet glycemic targets with dual/triple therapy, insulin therapy with basal insulin should be initiated and titrated to target. If the A1C remains above target, prandial insulin should be added. Consider initial injectable combination (i.e., GLP-1 RA plus basal insulin or prandial/basal insulin) if A1C is greater than 10% and 2% above target. Consider the early introduction of insulin if there is evidence of ongoing catabolism, if symptoms of hyperglycemia are present, or when A1C levels (greater than 10%) or blood glucose levels (300 mg/dL or more) are very high. In patients who are starting on insulin therapy and are taking a thiazolidinedione or sulfonylurea, discontinue or reduce the dose of the oral medication.[50321][60607][60608]
  • Numerous studies, including the Diabetes Control and Complications Trial (DCCT) and the UK Prospective Diabetes Study (UKPDS), have demonstrated that early intensive glycemic control reduces the risk of microvascular complications and may decrease the risk of macrovascular events.[50186][50188][19204][50196]
  • For routine use, insulin is administered via the subcutaneous route; however, the extent and rate of absorption of exogenous insulin from the subcutaneous tissue (such as the abdomen, upper arm, anterior and lateral aspects of the thigh, and buttocks) may be affected by a number of different factors, including blood perfusion, amount of adipose tissue at the injection site, depth of injection, temperature of the skin, and properties of the insulin molecule.[50195]

Comparative Efficacy

  • Insulin aspart, insulin lispro, and insulin glulisine are rapid-acting analogs that are considered equipotent to regular human insulin. When compared to human insulin in clinical trials, all rapid-acting analogs have demonstrated additional decreases in A1C, typically ranging from 0.1% to 0.2%. Greater reductions in post-prandial and fasting glucose levels also occur. When compared to each other, rapid-acting analogs produce similar clinical results.[50197][30573][50198][50199][50200]
  • Regular insulin is available in 2 concentrations: 100 units/mL and 500 units/mL. Both concentrations share a similar peak and onset of action, but U-500 insulin has a duration of action similar to that of NPH (up to 24 hours). Regular U-500 insulin has less day to day variation in absorption rates and less absorption variation from different body regions compared to regular U-100.[61947] This longer duration of action allows for administration of regular U-500 insulin 2 to 3 times per day; regular 100 units/mL is usually administered 3 or more times per day and may also be used in combination with oral antihyperglycemic agents or longer-acting insulin products.[44404][44405][60488]
  • Insulin glargine and insulin detemir are long-acting analogs that are considered equipotent to isophane insulin (NPH). Effects on A1C are typically similar to NPH, although some clinical trials have demonstrated significant differences in favor of the analogs. Fasting glucose levels have been significantly lower with the analogs when compared to NPH insulin in several (but not all) trials. No clinically relevant differences regarding glucose control have been demonstrated between insulin glargine and insulin detemir; however, to achieve equivalent glucose control insulin detemir is frequently injected twice daily at a higher dose.[50201][50206][50208][50209][50210]
  • Insulin degludec is a long-acting, once daily insulin that has a longer half-life (25.4 hours) than any other basal insulin. This long half-life lends itself to a duration of action that is at least 42 hours.[60594] In clinical trials, insulin degludec has been compared to insulin glargine; both insulins reduce A1C levels to a similar degree.[60591][60592][60595][60596]


Insulin Comparative Efficacy Trials





Home, et al. Diabet Med 2000;17:762-770.[50197]

Prospective, randomized, open-label parallel-group trial comparing insulin aspart (n = 698) and regular human insulin (n = 349) before main meals in Type 1 DM with NPH as basal insulin

Mean A1C after 6 months: Insulin aspart: 7.88 +/- 0.03 vs. regular insulin: 8 +/- 0.04; p less than 0.02

Slight improvements in preprandial and postprandial glucose concentrations for insulin aspart vs. regular insulin

Slight differences in glucose control exist between insulin aspart and regular human insulin. Insulin aspart may be advantageous to human insulin for long-term glucose control. 

Dailey, et al. Diabetes Care 2004;27:2363- 2368.[30573]

Phase III open-label, parallel group RCT comparing insulin glulisine (n = 435) to regular human insulin (n = 441) in Type 2 DM with NPH as basal insulin

Oral hypoglycemic use at randomization: 56.3% for insulin glulisine vs. 59.6% for regular human insulin

Mean A1C at 6.5 months: 7.11% for insulin glulisine vs. 7.22% for regular insulin, p = 0.0029

Mean post-prandial glucose levels at 6.5 months (glulisine vs. regular human insulin):

Breakfast: 156 vs. 162 mg/dL; p less than 0.05

Dinner: 154 vs. 163 mg/dL; p less than 0.05

Oral hypoglycemic use at endpoint (all treatment groups): 58.4%

Insulin glulisine in combination with NPH is associated with small improvements in glucose control relative to regular human insulin with NPH in Type 2 DM.

Roach P, et al. Clin Ther 1999;21:523-534.[50211]

Randomized, open-label crossover study comparing glycemic control between premixed lispro/lispro-protamine and human insulin mixtures (regular/NPH) in Type 1 and Type 2 DM

One group of each DM type received lispro mixtures first, followed by human mixtures. Other 2 groups received human mixtures followed by lispro mixtures.

Mean A1C at 6 months (all patients): Regular/NPH insulin: 7.57% vs. Lispro/lispro-protamine insulin: 7.72%; p = 0.107

Post-prandial levels (mmol/L) in all patients after breakfast: Regular/NPH insulin: 9.74 vs. Lispro/lispro-protamine insulin: 7.83; p is less than 0.001

Fasting glucose, post-prandial lunch and dinner glucose concentrations not significantly different between groups.

Insulin lispro mixtures provided similar overall glycemic control when compared to human insulin, and improved post-prandial control at breakfast.

Riddle, et al. Diabetes Care 2003;26:3080-3086.[50208]

Randomized, open-label parallel group trial comparing insulin glargine (n = 367) to NPH human insulin (n = 389) at bedtime in Type 2 DM; all patients required to have stable doses of 1 to 2 oral antidiabetes drugs for at least 3 months

Started with 10 units/kg for both insulins at bedtime; titrated weekly to target fasting plasma glucose 100 mg/dL or less

Over 70% taking both metformin and sulfonylurea at baseline

Mean daily dose at 6 months: Insulin glargine: 47.2 +/- 1.3 units vs. NPH: 41.8 +/- 1.3 units; p less than 0.05

Mean A1C at 6 months: Insulin glargine: 6.96% vs. NPH: 6.97%

A1C 7% or greater with no documented nocturnal hypoglycemia: Insulin glargine: 33.2% vs. NPH: 26.7%; p is less than 0.05

Fasting plasma glucose 100 mg/dL or less with no documented nocturnal hypoglycemia: Insulin glargine: 22.1% vs. NPH: 15.9%; p <is less than 0.03

Insulin glargine and NPH achieved similar A1C and fasting plasma glucose levels. Insulin glargine was associated with less hypoglycemia.

Home, et al. Diabetes Care 2004;27:1081-1087.[50206]

Randomized, open-label parallel group trial comparing insulin detemir to NPH human insulin in Type 1 DM with insulin aspart as meal time insulin

Insulin detemir (2 groups) regimens: Before breakfast and at bedtime (n = 139) or every 12 hours (n = 137)

NPH (1 group) regimen: Before breakfast and at bedtime (n = 132)

Mean A1C (SE) at 4 months: Insulin detemir before breakfast and bedtime: 7.78 +/- 0.07% vs. Insulin detemir at 12 h intervals: 7.75 +/- 0.07% vs NPH: 7.94 +/- 0.07%; p = 0.027 for both determir groups vs. NPH

Mean pre-breakfast plasma glucose at 4 months (mmol/L): Insulin detemir before breakfast and bedtime: 8.26 +/- 0.2 vs. insulin detemir at 12 h intervals: 8.28 +/- 0.2% vs. NPH: 9.05 +/- 0.21%; p = 0.005 for both detemir groups vs. NPH

Weight change (kg): Insulin detemir before breakfast and bedtime: 2.91 (95% CI 2.7 to 3.05) vs. insulin detemir at 12 h intervals: 2.95 (95% CI 2.8 to 3.1) vs. NPH: 3.49 (95% CI 3.31 to 3.68); p less than 0.001 for both detemir groups vs. NPH

Insulin detemir was superior to NPH for overall glucose control when used in a basal bolus regimen with insulin aspart. Significantly less weight gain occurred with insulin detemir.

Heller, et al. Lancet 2012;379:1489. [60595]

Randomized, controlled, open-label, treat to target, non-inferiority 52-week trial comparing treatment with once-daily insulin degludec (n = 472) to once-daily insulin glargine (n = 157) in Type 1 DM with insulin aspart as meal time insulin

Patients were receiving basal-bolus insulin therapy for at least one year prior to study initiation.

Reduction in A1C after 1 year: 0.40% points for insulin degludec and 0.39% points for insulin glargine,(estimated treatment difference –0.01% [95% CI –0.14 to 0.11]; p less than 0.0001 for non-inferiority testing)

A1C less than 7% after 1 year: 40% insulin degludec vs 43% insulin glargine

Rates of overall confirmed hypoglycemia (PG less than 3.1 mmol/L or severe): insulin degludec 42.54 vs. insulin glargine 40.18 episodes per patient-year of exposure; estimated rate ratio 1.07 [0.89 to 1.28]; p = 0.48)

Rate of nocturnal confirmed hypoglycemia: 25% lower with degludec than with glargine (4.41 vs. 5.86 episodes per patient-year of exposure; rate ratio 0.75 [0.59 to 0.96]; p = 0.021)

Overall serious adverse event rates: 14 vs 16 events per 100 patient-years of exposure for the insulin degludec and insulin glargine groups

Reduction in A1C from baseline with insulin degludec and insulin glargine was similar, thus establishing non-inferiority of insulin degludec to insulin glargine in improving long-term glycemic control in Type 1 diabetes. Insulin degludec also exhibited a decreased risk of nocturnal hypoglycemia.

Zinman, et al. Diabetes Care 2012;35:2464-2471.[60592]

Randomized, open-label, treat-to-target 52-week trial comparing insulin degludec with glargine for efficacy and safety in insulin-naive patients with Type 2 DM inadequately controlled with oral antidiabetic drugs (OADs)

Patients with A1C of 7 to 10% were randomized to receive once daily degludec (n = 773) or glargine (n = 257), both with metformin. Insulin was titrated to achieve pre-breakfast plasma glucose (PG) of 3.9-4.9 mmol/L

Reduction in A1C after 1 year: insulin degludec 1.06% vs. insulin glargine 1.19%, (estimated treatment difference 0.09%) [95% CI -0.04 to 0.22)

Rates of overall confirmed hypoglycemia (PG less than 3.1 mmol/L or severe episodes requiring assistance): insulin degludec 1.52 vs insulin glargine 1.85 episodes per patient-year of exposure

Rate of nocturnal confirmed hypoglycemia: insulin degludec 0.25 vs. insulin glargine 0.39 episodes per patient-year of exposure; p = 0.038

A1C less than 7% without hypoglycemia: insulin degludec 42% vs insulin glargine 46%; P = 0.34

End-of-trial mean daily insulin doses: 0.59 units/kg for insulin degludec and 0.60 units/kg for insulin glargine

Adverse event rates were similar

Insulins degludec and glargine administered once daily in combination with OADs provided similar long-term glycemic control in insulin-naive patients with Type 2 diabetes, with lower rates of nocturnal hypoglycemia with degludec.

Bode, et al. Diabetes Care 2015.[60598]

Randomized, open-label, non-inferiority 24-week trial comparing the change in A1C with prandial inhaled insulin (n = 174) to that of subcutaneous aspart (n = 171), both with basal insulin, in patients with Type 1 DM and A1C 7.5 to 10%

Trial included an initial 4-week basal insulin optimization period for titration of basal insulin dose to a goal FPG level 100 to 120 mg/dL. Mealtime insulin was switched to insulin aspart. Throughout the trial, patients remained on their pre-enrollment basal insulin

Mean change in A1C at 24 weeks: inhaled insulin (–0.21%) vs. insulin aspart (–0.40%). The between-group difference was 0.19% (2.1 mmol/mol) (95% CI 0.02 to 0.36).

A1C less than 7% after 24 weeks: insulin aspart 30.7% vs. inhaled insulin 18.3%

Weight change: inhaled insulin patients had a small weight loss (–0.4 kg) compared with a gain (+0.9 kg) for aspart patients (p = 0.0102)

Rates of hypoglycemia: inhaled insulin patients had a lower hypoglycemia event rate than aspart patients (9.8 vs. 14 events/patient-month, p less than 0.0001)

Adverse Events: Cough (generally mild) was the most frequent adverse event (inhaled insulin 31.6% vs. insulin aspart 2.3%)

In patients with Type 1 DM receiving basal insulin, A1C reduction with inhaled insulin was non-inferior to that of aspart, with less hypoglycemia and less weight gain but increased incidence of cough.

Fulcher, et al. Diabetes Care 2014.[60600]

Randomized, open-label, multinational, treat-to-target 26-week trial comparing insulin degludec; insulin aspart with biphasic insulin aspart 70/30 in adults with Type 2 DM inadequately controlled with once- or twice-daily pre- or self-mixed insulin with or without oral antidiabetic drugs. Patients continued on pre-trial oral background therapies which may have included any of the following used alone or in combination: metformin, pioglitazone, DPP-4inhibitor throughout the entire trial

Patients received twice daily injections of insulin degludec; insulin aspart (n = 224) or biphasic insulin aspart 70/30 (n = 222), administered with breakfast and the main evening meal and dose titrated to a self-measured premeal PG target of 4 to 5 mmol/L

Mean A1C at 26 weeks: 7.1% for both groups, with insulin degludec; insulin aspart achieving the prespecified non-inferiority margin for mean change in A1C (estimated treatment difference [ETD] –0.03% points [95% CI –0.18 to 0.13])

Reduction in Fasting PG: treatment with insulin degludec; insulin aspart was superior in lowering fasting PG (ETD –1.14 mmol/L [95% CI –1.53 to –0.76], p less than 0.001) and had a significantly lower final mean daily insulin dose (estimated rate ratio 0.89 [95% CI 0.83 to 0.96], p = 0.002)

Rates of hypoglycemia: fewer confirmed, nocturnal confirmed, and severe hypoglycemia episodes were reported for insulin degludec; insulin aspart compared with biphasic insulin aspart 70/30

Twice daily treatment with insulin degludec; insulin aspart effectively improves A1C and fasting PG levels with fewer hypoglycemia episodes versus biphasic insulin aspart 70/30 in patients with uncontrolled Type 2 DM previously treated with once- or twice-daily pre- or self-mixed insulin.

Adverse Reactions/Toxicities


It is estimated that 90% of all patients receiving insulin will experience a hypoglycemic event. Although difficult to define in quantitative terms, plasma glucose of less than 60 mg/dL after an overnight fast and plasma glucose of less than 50 mg/dL after a carbohydrate meal are generally considered to be below normal.[50212] Hypoglycemia can manifest as hunger, pallor, nausea or vomiting, fatigue, diaphoresis, headache, palpitations, numbness of the mouth, tingling in the fingers, tremor, muscle weakness, blurred vision, hypothermia, uncontrolled yawning, irritability, mental confusion, sinus tachycardia, shallow breathing, and loss of consciousness. It should be noted hypoglycemia unawareness, a condition in which patients are less aware that they are hypoglycemic, is increased in patients with a long history of diabetes due to autonomic nervous system dysfunction or taking beta-blockers. Data from clinical trials suggest that use of rapid-acting (insulin aspart, insulin glulisine, and insulin lispro) and basal insulin analogs (insulin detemir, insulin glargine, and insulin degludec) may result in a decreased risk of hypoglycemia compared with traditional human insulin. Insulin degludec has been shown to have a significantly lower rate of nocturnal hypoglycemia compared to insulin glargine in both Type 1 and Type 2 DM.[60592][60595][60602][60604] However, rates of overall hypoglycemia have only been shown to be significantly lower in patients with Type 2 DM; patients with Type 1 DM had a slightly higher rate of hypoglycemia with insulin degludec compared to insulin glargine.[60604] All patients receiving insulin should receive education about the signs and symptoms of hypoglycemia and have action plans for glucose correction.[50197][50208][30647][50214][50216][50217]

Weight gain

Excess weight gain may occur with insulin therapy; the amount of weight gain varies with the intensity of the insulin treatment regimen utilized. In the Diabetes Control and Complications Trial (DCCT), patients who were treated with an intensive insulin regimen gained 4.75 kg more than patients on conventional therapy. Insulin detemir is associated with less weight gain than insulin glargine or NPH insulin. A meta-analysis directly comparing detemir and glargine demonstrated a significant difference of 0.91 kg weight gain between the drugs. In a trial comparing inhaled insulin to insulin aspart, patients using insulin aspart experienced a 0.9 kg weight gain (p = 0.0102) in contrast to patients using inhaled insulin, who experienced a small weight loss.[60598] The risk of any potential weight gain should be balanced by the benefits from improved glycemic control.[19204][50201][50206][50219][50220][50221]

Injection site reactions

Injection site reactions such as lipohypertrophy and lipoatrophy can occur following subcutaneous administration of insulin. Lipodystrophy reactions can be avoided by rotating the sites of injection so that a site is not used more than once every 1 to 2 months.

Insulin resistance

Insulin resistance may develop in patients requiring daily insulin injections. Exogenously administered insulin has the ability to cause anti-insulin antibodies, which may cause chronic insulin resistance in patients with Type 1 DM. If hyperglycemia resulting from apparent chronic insulin resistance due to anti-insulin antibodies is present, changing the insulin source to a less antigenic product may be helpful. Corticosteroids have been used if changing to a different insulin species source is not effective. In patients with Type 2 DM, insulin resistance is usually associated with obesity and a decrease in tissue sensitivity to insulin. Treatments for Type 2 DM include weight loss and or institution of insulin-sensitizing drugs such as metformin or a thiazolidinedione.[30440]

Drug Interactions

Antidiabetic drugs

The risk of hypoglycemia may increase with the use of insulin in combination with other antidiabetic agents such as alpha-glucosidase inhibitors, metformin, thiazolidinediones, or oral sulfonylureas. In addition, pioglitazone and troglitazone should be administered with caution as the combined use of insulin with these drugs significantly increases the risk of heart failure or edema.


Beta-blockers can inhibit the compensatory actions of epinephrine's response to hypoglycemia. As such, hypoglycemia can be prolonged. Additionally, beta-blockers can mask the signs and symptoms of hypoglycemia, especially tachycardia. Beta-blockers have also been associated with increasing blood glucose concentrations. While beta-blockers may have negative effects on glycemic control, they reduce the risk of cardiovascular disease and stroke in patients with diabetes.[51005] Furthermore, their use should not be avoided in patients with compelling indications for beta-blocker therapy (i.e., post-MI, heart failure, etc.) when no other contraindications are present. Decreased mortality has been shown in the post-MI and heart failure populations when beta-blockers are used, especially in patients with coexisting diabetes mellitus.[50223]


Thiazide diuretics can decrease the hypoglycemic effects of insulin by producing an increase in blood glucose levels. It appears that the effects of thiazides on glucose control are dose-dependent and low doses can be used without significant effects. Patients on insulin therapy should be monitored for changes in blood glucose control. Insulin dosage adjustments may be necessary.[50223]

Other anti-hypertensive drugs

Angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists, and guanethidine may enhance the hypoglycemic effects of insulin. Patients should therefore be monitored closely for changes in glycemic control.[50223][21961][42591]

Safety Issues


Insulin is contraindicated during episodes of hypoglycemia. Patients at risk for hypoglycemia include those who are geriatric or who have brittle diabetes, have received an overdose of insulin, have a delayed or decreased food intake, or are undergoing an excessive amount of exercise relative to their usual insulin dose. Additionally, patients with renal impairment may be at increased risk of hypoglycemia.


Special attention must be given to caloric intake, insulin dosage adjustments, and avoidance of low blood glucose concentrations during the treatment of children and infants receiving insulin. Because children may not be able to identify symptoms of hypoglycemia, target plasma glucose concentrations and A1C treatment goals are higher compared to adult patients.[50226][54796]

Acute Bronchospasm

Inhaled insulin is contraindicated in patients with chronic pulmonary disease, such as asthma or chronic obstructive pulmonary disease (COPD) because of the risk of acute bronchospasm in these patients. Prior to initiating therapy with inhaled insulin, perform a detailed medical history, physical examination, and spirometry (FEV1) to identify potential lung disease in all patients. Assess pulmonary function (e.g., spirometry) after the first 6 months of therapy, and annually thereafter, even in the absence of pulmonary symptoms. In patients who have a decline of 20% or greater in FEV1 from baseline, consider discontinuing inhaled insulin. Consider more frequent monitoring of pulmonary function in patients with pulmonary symptoms such as wheezing, bronchospasm, breathing difficulties, or persistent or recurring cough. If symptoms persist, discontinue inhaled insulin.[57572]

[19204]UK Prospective Diabetes Study (UKPDS) Group. Effect of intensive blood-glucose control with metformin on complications in overweight patients with type 2 diabetes (UKPDS 34). Lancet. 1998;352:854-65

[21961]Pandit MK, Burke J, Gustafson AB, et al. Drug-induced disorders of glucose tolerance. Ann Intern Med 1993;118(7):529-539.

[22299]Novolog (insulin aspart) injection package insert. Princeton, NJ: Novo Nordisk, Inc; 2021 March.

[30440]Reynolds NA, Wagstaff AJ. Insulin aspart: a review of its use in the management of type 1 or type 2 diabetes mellitus. Drugs 2004;64:1957-74.

[30510]Humalog (insulin lispro) package insert. Indianapolis, IN: Eli Lilly and Company; 2019 Nov.

[30573]Dailey G, Rosenstock J, Moses RG, et al. Insulin glulisine provides improved glycemic control in patients with type 2 diabetes. Diabetes Care 2004;27:2363-8.

[30647]Hirsch IB. Insulin analogues. N Engl J Med 2005;352:174-83.

[34541]Holman RR, Paul SK, Bethel MA, et al. 10-year follow-up of intensive glucose control in type 2 diabetes. N Engl J Med 2008;359:1577-89.

[40554]Novolog Mix (insulin aspart protamine and insulin aspart) injection package insert. Princeton, NJ: Novo Nordisk, Inc; 2021 April.

[42591]Scheen AJ. Drug Interactions of Clinical Importance with Antihyperglycemic Agents. Drug Saf 2005;28:601-631.

[44086]Lantus (insulin glargine [rDNA origin] injection) solution for subcutaneous injection package insert. Bridgewater, NJ: Sanofi-Aventis U.S. LLC; 2019 Nov.

[44404]Novolin R (regular human insulin injection) package insert. Princeton, NJ: Novo Nordisk; 2018 May.

[44405]Humulin R (regular human insulin injection) package insert. Indianapolis, IN: Lilly USA, LLC; 2019 Nov.

[50185]Qayyum R, Bolen S, Maruthur N, et al. Systematic review: comparative effectiveness and safety of premixed insulin analogues in type 2 diabetes. Ann Intern Med 2008;149:549-559.

[50186]Diabetes Control and Complications Trial Research Group. The effect of intensive diabetes treatment on the development and progression of long-term complications in insulin-dependent diabetes mellitus: the Diabetes Control and Complications Trial. N Engl J Med 1993;329:977-986.

[50187]Reichard P, Nilsson BY, Rosenqvist U. The effect of long-term intensified insulin treatment on the development of microvascular complications of diabetes mellitus. N Engl J Med 1993;329:304-309.

[50188]UK Prospective Diabetes Study (UKPDS) Group. Intensive blood glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complication in patients with type 2 diabetes (UKPDS 33). Lancet 1998;352:837-853.

[50189]Ohkubo Y, Kishikawa H, Araki E, et al. Intensive insulin therapy prevents the progression of diabetic microvascular complications in Japanese patients with NIDDM: a randomized prospective 6-year study. Diabetes Res Clin Pract 1995;28:103-117.

[50190]Ray KK, Seshasai SR, Wijesuriya S, et al. Effect of intensive control of glucose on cardiovascular outcomes and death in patients with diabetes mellitus: a meta-analysis of randomised controlled trials. Lancet 2009;373:1765-1772.

[50191]Turnbull FM, Abraira C, Anderson RJ, et al. Intensive glucose control and macrovascular outcomes in type 2 diabetes. Diabetologia 2009;52:2288-2298.

[50195]Davis S, Granner D. Insulin, oral hypoglycemic agents, and the pharmacology of the endocrine pancreas. In: Hardman JG, Limbird LE, eds. Goodman and Gilman's: The Pharmacologic Basis of Therapeutics. 9th ed. New York, NY: McGraw-Hill; 1996: 1487-1518.

[50196]Nathan DM, Cleary PA, Backlund JY, et al. Intensive diabetes treatment and cardiovascular disease in patients with type 1 diabetes. N Engl J Med 2005;353:2643-53.

[50197]Home PD, Lindholm A, Riist A, et al. Insulin aspart vs human insulin in the management of long-term blood glucose control in type 1 diabetes mellitus: a randomized controlled trial. Diabet Med 2000;17:762-770.

[50198]van Bon AC, Bode BW, Sert-Langeron C, et al. Insulin glulisine compared to insulin aspart and to insulin lispro administered by continuous subcutaneous insulin infusion in patients with type 1 diabetes: a randomized controlled trial. Diabetes Technol Ther 2011;13:607-614.

[50199]Philotheou A, Arslanian S, Blatniczky L, et al. Comparable efficacy and safety of insulin glulisine and insulin lispro when given as part of a basal-bolus insulin regimen in a 26-week trial in pediatric patients with type 1 diabetes. Diabetes Technol Ther 2011;13:327-334.

[50200]Dreyer M, Prager R, Robinson A, et al. Efficacy and safety of insulin glulisine in patients with type 1 diabetes. Horm Metab Res 2005;37:702-707

[50201]Swinnen SG, Simon ACR, Holleman F, et al. Insulin detemir versus insulin glargine for type 2 diabetes mellitus. Cochrane Database of Systematic Reviews 2011; Issue 7.

[50206]Home, P, Bartley P, Russell-Jones D, et al. Insulin detemir offers improved glycemic control compared with NPH insulin in people with type 1 diabetes: a randomized clinical trial. Diabetes Care 2004;27:1081-1087.

[50208]Riddle MC, Rosenstock J, Gerich J, et al. The treat-to-target trial: randomized addition of glargine or human NPH insulin to oral therapy of type 2 diabetic patients. Diabetes Care 2003;26:3080-3086.

[50209]Ratner RE, Hirsch IB, Jeifing JL, et al. Less hypoglycemia with insulin glargine in intensive insulin therapy for type 1 diabetes. Diabetes Care 2000;23:639-643.

[50210]Russell-Jones D, Simpson R, Hylleberg B, et al. Effects of QD insulin detemir or neutral protamine hagedorn on blood glucose control in patients with type 1 diabetes mellitus using a basal-bolus regimen. Clin Ther 2004;26:724-736.

[50211]Roach P, Trautmann M, Arora V, et al. Improved postprandial blood glucose control and reduced nocturnal hypoglycemia during treatment with two novel insulin lispro-protamine formulations, insulin lispro mix25 and insulin lispro mix50. Mix50 Study Group. Clin Ther 1999;21:523-534.

[50212]Amiel SA, Tamborlane WV, Sacca L, Sherwin RS. Hypoglycemia and glucose counterregulation in normal and insulin-dependent diabetic subjects. Diabetes Metab Rev 1988;4:71-89.

[50214]Raymond G, Profozic V, Middle M. Insulin glulisine imparts effective glycaemic control in patients with type 2 diabetes. Dibetes Res Clin Pract 2007; 76:304-312

[50216]Bretzel RG, Arnolds S, Medding J, et al. A direct efficacy and safety comparison of insulin aspart, human soluble insulin, and human premix insulin (70/30) in patients with type 2 diabetes. Diabetes Care 2004;27:1023-1027

[50217]Hermansen K, Davies M, Derezinski T, et al. A 26-week, randomized, parallel, treat-to-target trial comparing insulin detemir with NPH insulin as add-on therapy to oral glucose-lowering drugs in insulin-naive people with type 2 diabetes. Diabetes Care 2006;29:1269-1274.

[50219]Diabetes Control and Complications Trial (DCCT) Research Group. Influence of intensive diabetes treatment on body weight and composition of adults with type 1 diabetes in the Diabetes Control and Complications Trial. Diabetes Care 2001;24:1711-21

[50220]Henry RR, Gumbiner B, Ditzler T, et al. Intensive conventional insulin therapy for type II diabetes. Metabolic effects during a 6-mo outpatient trial. Diabetes Care 1993;16:21-31.

[50221]Raslova K, Can Tamer S, Clauson P, et al. Insulin detemir results in less weight gain than NPH insulin when used in basal-bolus therapy for type 2 diabetes mellitus, and this advantage increases with baseline body mass index. Clin Drug Invest 2007;27:279-285.

[50223]Tsiodras S, Mantzoros C, Hammer S, et al. Effects of protease inhibitors on hyperglycemia, hyperlipidemia, and lipodystrophy: a 5-year cohort study. Arch Intern Med 2000;160(13):2050-2056.

[50226]American Diabetes Association. Standards of medical care in diabetes-2012. Diabetes Care 2012;35(suppl1):S11-S63.

[50277]Levemir (insulin detemir [rDNA origin]) injection package insert. Princeton, NJ: Novo Nordisk, Inc; 2019 Dec.

[50321]Davies MJ, D'Alessio DA, Fradkin J, et al. Management of hyperglycemia in Type 2 Diabetes, 2018. A Consensus Report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD). Diabetes Care 2018;41:2669-2701.

[51005]Lovallo W, Wilson MF, Vincent AS, et al. Blood pressure response to caffeine shows incomplete tolerance after short-term regular consumption. Hypertension 2004;43:760-765.

[51122]Humalog (insulin lispro protamine; insulin lispro mix 50/50) package insert. Indianapolis, IN: Eli Lilly and Company; 2019 Nov.

[51123]Humalog (insulin lispro protamine; insulin lispro mix 75/25) package insert. Indianapolis, IN: Eli Lilly and Company; 2019 Nov.

[51227]Apidra (insulin glulisine [rDNA origin]) injection package insert. Bridgewater, NJ: Sanofi-Aventis US LLC; 2019 Nov.

[54173]Novolin R (regular human insulin injection) package insert. Plainsboro, NJ: Novo Nordisk Inc.; 2019 Nov.

[54477]Novolin N (human insulin isophane suspension injection) package insert. Princeton, NJ: Novo Nordisk; 2019 Nov.

[54796]American Diabetes Association. Standards of medical care in diabetes-2015. Diabetes Care 2015;38(suppl1):S1-S94.

[57572]Afrezza (Inhaled Insulin) package insert. Danbury, CT: MannKind Corp; 2018 Oct.

[58899]Toujeo (insulin glargine injection) solution for subcutaneous injection package insert. Bridgewater, NJ: Sanofi-Aventis U.S. LLC; 2019 Nov.

[60172]Tresiba (insulin degludec) injection package insert. Plainsboro, NJ: Novo Nordisk Inc.; 2019 Nov.

[60453]Basaglar (insulin glargine [rDNA origin] injection) solution for subcutaneous injection package insert. Indianapolis, IN: Eli Lilly and Company; 2019 Nov.

[60488]Humulin R U-500 (regular insulin human injection) package insert. Indianapolis, IN: Lilly USA, LLC. 2019 Nov.

[60591]Zinman B, Prillis-Tsimikar A, Cariou B, et al. Insulin degludec versus glargine in insulin naive patients with type 2 diabetes: a randomized treat to target trial (BEGIN Once Long). Diabetes Care 2012;35:2464–2471.

[60592]Zinman B, Prillis-Tsimikar A, Cariou B, et al. Insulin degludec versus glargine in insulin naive patients with type 2 diabetes: a randomized treat to target trial (BEGIN Once Long). Diabetes Care 2012;35:2464–2471.

[60594]Haahr H , Heise T. A review of the pharmacological properties of insulin degludec and their clinical relevance. Clin Pharmacokinet 2014;53:787—800.

[60595]Heller S, Buse J, Fisher M, et al. Insulin degludec, an ultra-longacting basal insulin, versus insulin glargine in basal-bolus treatment with mealtime insulin aspart in type 1 diabetes (BEGIN Basal-Bolus Type 1): a phase 3, randomised, open-label, treat-to-target non-inferiority trial. Lancet 2012;379:1489.

[60596]Meneghini L, Atkin SL, Gough SC, et al. The efficacy and safety of insulin degludec given in variable once-daily dosing intervals compared with insulin glargine and insulin degludec dosed at the same time daily: a 26-week, randomized, open-label, parallel-group, treat-to-target trial in individuals with type 2 diabetes. Diabetes Care 2013;36:858—64.

[60598]Bode BW, McGill JB, Lorber DL, et al. Inhaled Technosphere insulin compared with injected prandial insulin in type 1 diabetes: a randomized 24-week trial. Diabetes Care 2015. Epub ahead of print,doi:10.2337/dc15-0075.

[60600]Fulcher GR, Christiansen JS, Bantwal G, et al. Comparison of insulin degludec/insulin aspart and biphasic insulin aspart 30 in uncontrolled, insulin-treated type 2 diabetes: a phase 3a, randomized, treat-to-target trial. Diabetes Care 2014;37:2084-90.

[60602]Russell-Jones D, Gall MA, Niemeyer M, et al. Insulin degludec results in lower rates of nocturnal hypoglycaemia and fasting plasma glucose vs. insulin glargine: A meta-analysis of seven clinical trials. Nutr Metab Cardiovasc Dis 2015;25:898-905.

[60604]Ratner RE, Gough SC, Mathieu C, et al. Hypoglycaemia risk with insulin degludec compared with insulin glargine in type 2 and type 1 diabetes: a pre-planned meta-analysis of phase 3 trials. Diabetes Obes Metab 2013;15:175-84.

[60607]American Diabetes Association. Standards of Medical Care in Diabetes - 2019. Diabetes Care. 2019; 42(Suppl 1):S1.

[60608]Garber AJ, Abrahamson MJ, Barzilay JI, et al. Consensus Statement by The American Association of Clinical Endocrinologists and American College of Endocrinology on the Comprehensive Type 2 Diabetes Management Algorithm 2019 Executive Summary. Endocrine Pract 2019;25:69-100.

[61947]Cochran E, Musso C, Gorden P. The use of U-500 in patients with extreme insulin resistance. Diabetes Care 2005;28:1240-4.

[62395]Fiasp (insulin aspart) injection package insert. Plainsboro, NJ: Novo Nordisk, Inc; 2019 Dec

[62517]Fiasp (insulin aspart injection), European package insert. Bagsvaerd Denmark: Novo Nordisk A/S; 2017 Jan.

[62674]Admelog (insulin lispro) package insert. Bridgewater, NJ: sanofi-aventis U.S. LLC; 2019 Nov.

[63144]American Diabetes Association (ADA). Consumer Guide 2017 - Medications. March/April Diabetes Forecast 2017. Available at: www.main.diabetes.org/dforg/pdfs/2017/2017-cg-medications.pdf Accessed: May 2018.

[65982]Semglee (insulin glargine [rDNA origin] injection) solution for subcutaneous injection package insert. Morgantown, WV: Mylan Pharmaceuticals, Inc.; 2020 Jun.