Diabetes is a disorder of blood sugar levels. It occurs because insulin in the body does not work effectively. As a result, the body struggles to regulate blood sugar levels.
A person can manage type 2 diabetes with lifestyle measures, oral medication, injections, and also insulin if other treatments are not successful.
There are so many medications available for diabetes that it can be difficult knowing which is best. This article will explain the different types of medication available, as well as their effects on the body.
Treatment for type 1 diabetes always involves insulin. This replaces absent insulin and keeps blood sugar levels steady.
People can self-inject insulin under the skin, or, if hospitalized, a doctor might inject insulin directly into the blood. It is also available as a powder that people can breathe in. Some people prefer to use insulin pumps, which are small devices that send insulin through tubes inserted into the skin.
Insulin injections vary by how quickly they act, their peak action, and how long they last. The aim is to mimic how the body would produce insulin throughout the day to promote efficient energy intake.
There are several different types of insulin.
Rapid-acting injections take effect within 5 to 15 minutes but last for a shorter time of 2 to 4 hours:
- insulin lispro (Humalog)
- insulin aspart (NovoLog)
- insulin glulisine (Apidra)
Short-acting injections take effect from between 30 minutes and 1 hour, and last for 3 to 8 hours:
Intermediate-acting injections take effect after about 1 to 4 hours, and last for 12 to 18 hours:
Long-acting injections take effect after 1 or 2 hours and last for between 14 and 24 hours:
- insulin glargine (Toujeo)
- insulin detemir (Levemir)
- insulin degludec (Tresiba)
Premixed injections are combinations of the above types of insulin. All take effect from between 5 minutes and 1 hour, and last for between 10 and 24 hours:
- insulin lispro protamine and insulin lispro (Humalog Mix50/50 and Humalog Mix75/25)
- insulin aspart protamine and insulin aspart (NovoLog Mix 50/50 and NovoLog Mix 70/30)
- NPH insulin and regular insulin (Humulin 70/30 and Novolin 70/30)
People can breathe in rapid-acting inhalable insulin, which takes effect within 12 to 15 minutes and lasts for 2.5 to 3 hours:
- Insulin human powder (Afrezza)
Other drugs for type 1 diabetes
The following drugs, non-insulin injectables, are also common for people treating type 1 diabetes:
- Amylin analogs: Pramlintide (Symlin) mimics another hormone, amylin, that plays a role in glucose regulation.
- Glucagon can reverse blood sugar levels when they fall too low as a result of insulin treatment.
Insulin can also help manage high blood glucose levels in type 2 diabetes, but doctors typically prescribe it only when other treatments have not had the desired effect.
Women with type 2 diabetes who become pregnant may also use it to reduce the effects of the condition on the fetus.
In people with high blood glucose levels in spite of applying lifestyle measures to bring them down, doctors can prescribe non-insulin drugs to lower blood glucose. These drugs are listed below.
Many of the drugs have a combination of effects. If a person needs two or more treatments to manage glucose levels, insulin treatment may be necessary.
These drugs improve the secretion of insulin into the blood by the pancreas. People use the following newer medicines most often, as they are less likely to cause adverse effects:
- glimepiride (Amaryl)
- glipizide (Glucotrol)
- glyburide (DiaBeta, Micronase, Glynase)
The older, less common sulfonylureas are:
- chlorpropamide (Diabinese)
- tolazamide (Tolinase)
- tolbutamide (Orinase)
Today, doctors prescribe sulfonylureas less often than they did in the past. This is because they can cause very low blood sugar, which causes other health problems.
Meglitinides also enhance insulin secretion. These might also improve the effectiveness of the body in releasing insulin during meals, and include:
- nateglinide (Starlix)
- repaglinide (Prandin)
Biguanides boost the effect of insulin. They reduce the amount of glucose the liver releases into the blood.
They also increase the uptake of blood glucose into the cells.
Metformin is the only licensed biguanide in the United States, in the form of Glucophage, Glucophage XR, Glumetza, Riomet, and Fortamet.
Thiazolidinediones reduce the resistance of tissues to the effects of insulin. They have been associated with serious side effects, so they need monitoring for potential safety issues. People with heart failure should not use these medications, which include.
- pioglitazone (Actos)
- rosiglitazone (Avandia)
Alpha-glucosidase inhibitors cause carbohydrates to be digested and absorbed more slowly. This lowers glucose levels in the blood after meals.
- acarbose (Precose)
- miglitol (Glyset)
Dipeptidyl peptidase inhibitors
Dipeptidyl peptidase (DPP-4) inhibitors slow the rate of the stomach contents emptying further along the gut, and so slow down glucose absorption.
- alogliptin (Nesina)
- linagliptin (Tradjenta)
- sitagliptin (Januvia)
- saxagliptin (Onglyza)
Sodium-glucose co-transporter 2 inhibitors
Sodium-glucose co-transporter 2 (SGLT2) inhibitors cause the body to expel more glucose into the urine from the bloodstream. They might also lead to a modest amount of weight loss, which can be a benefit for type 2 diabetes.
- canagliflozin (Invokana)
- dapagliflozin (Farxiga)
- empagliflozin (Jardiance)
- ertugliflozin (Steglatro)
Incretin mimetics are drugs that mimic the hormone incretin, which stimulates insulin release after meals. These include:
- exenatide (Byetta, Bydureon)
- liraglutide (Victoza)
- dulaglutide (Trulicity)
- lixisenatide (Adlyxin)
- semaglutide (Ozempic)
Oral combination drugs
A variety of products that combine some of the drugs mentioned above is available. These include:
- alogliptin and metformin (Kazano)
- alogliptin and pioglitazone (Oseni)
- glipizide and metformin (Metaglip)
- glyburide and metformin (Glucovance)
- linagliptin and metformin (Jentadueto)
- pioglitazone and glimepiride (Duetact)
- pioglitazone and metformin (Actoplus MET, Actoplus MET XR)
- repaglinide and metformin (PrandiMet)
- rosiglitazone and glimepiride (Avandaryl)
- rosiglitazone and metformin (Avandamet)
- saxagliptin and metformin (Kombiglyze XR)
- sitagliptin and metformin (Janumet and Janumet XR)
The U.S. Food and Drug Administration has approved one ergot alkaloid, bromocriptine (Cycloset), for type 2 diabetes.
Doctors do not often recommend or prescribe this medication.
People use bile acid sequestrants to manage cholesterol levels, but they can also help maintain steady blood sugar levels. Only colesevelam (Welchol) has approval for type 2 diabetes.
Some drugs may help to prevent the complications of diabetes.
To treat high blood pressure, a doctor may prescribe ACE inhibitors or angiotensin II receptor blockers. These drugs also help prevent or manage kidney complications of diabetes.
People can manage the cardiovascular risks of diabetes, such as heart disease and stroke, by taking statins to lower cholesterol levels and a low-dose aspirin once every day if their doctor recommends it.
Losing weight is a key part of diabetes management and prevention. A doctor might suggest medicines to help with this, too, if lifestyle measures have not led to improvements.
- Lorcaserin (Belviq), which increases the feeling of being full after food and helps treat the obesity that often accompanies diabetes.
- Orlistat (Alli and Xenical) reduces the amount of fat absorbed from the diet and also supports weight loss.
- Phentermine and topiramate (Qsymia) is a combination drug that suppresses appetite and is an approved treatment for obesity.
Current guidelines urge doctors to look at each person's situation and suggest the best approach for the individual.
For people with cardiovascular disease
For people with both type 2 diabetes and atherosclerotic cardiovascular disease (CVD), 2018 guidelines recommend including the following as part of the antihyperglycemic treatment:
- sodium-glucose cotransporter 2 inhibitors (SGLT2)
- or glucagon-like peptide 1 receptor agonists (GLP1-RA)
For those with type 2 diabetes, atherosclerotic CVD and heart failure or a high risk of heart failure, doctors should prescribe:
- sodium-glucose cotransporter 2 inhibitors
For people with type 2 diabetes and chronic kidney disease, the guidelines urge doctors to consider using:
- a sodium-glucose cotransporter 2 inhibitor
- or glucagon-like peptide 1 receptor agonist
There is evidence that these can stop chronic kidney disease, CVD, or both, from getting worse.
People cannot take insulin orally because the stomach breaks down the hormone. This means the main ways for insulin to reach the bloodstream are injection or insulin pump.
Diabetes researchers have explored way, but these new methods require more study before wider use.
Possible future delivery methods for insulin include:
- by nasal or spray across the mucous membranes, the surfaces inside the nose
- through patches on the skin
The idea of an artificial pancreas is an ongoing area of research. This would use sensors to monitor blood sugar levels electronically and release the amount of insulin needed.
Surgeons could also transplant insulin-producing pancreatic cells from donors. Some people already benefit from the early progress of research into islet cell transplants.
Personalized medicine is a promising area for the treatment of all types of diabetes. Better grouping of the diseases and more targeted treatment may result from the developments in genetics and big data.