The most widely used diabetes medications span several drug classes, from the affordable generic metformin to newer injectable options like semaglutide and tirzepatide. Each works differently to lower blood sugar, and many now offer benefits beyond glucose control, including weight loss, heart protection, and kidney support. Here are the 10 medications you’re most likely to encounter.
1. Metformin (Glucophage)
Metformin is the most commonly prescribed glucose-lowering medication worldwide and the recommended first-line treatment in every major clinical guideline. It works by reducing the amount of sugar your liver releases into your bloodstream and helping your body use insulin more effectively. It’s available as a cheap generic, often costing under $10 per month, which makes it the default starting point for most people diagnosed with type 2 diabetes.
Side effects are mostly digestive: nausea, bloating, and diarrhea, especially in the first few weeks. An extended-release version reduces these problems for most people. Metformin doesn’t cause weight gain, which sets it apart from several older diabetes drugs, and some people lose a modest amount of weight on it.
2. Semaglutide Injection (Ozempic)
Semaglutide is a GLP-1 receptor agonist, meaning it mimics a gut hormone that triggers insulin release after meals and slows digestion. Ozempic is the injectable version approved for type 2 diabetes, given as a once-weekly self-injection. At higher doses, semaglutide can produce 10% to 20% body weight loss, making it one of the most effective options for people who need both glucose and weight management.
GLP-1 receptor agonists as a class also reduce the risk of major cardiovascular events (heart attack, stroke, and cardiovascular death) by about 14% compared to placebo. The most common side effects are nausea, vomiting, and diarrhea, which tend to improve over time. Cost is a significant barrier: the U.S. list price runs close to $970 per month, though insurance coverage and manufacturer coupons can lower that considerably.
3. Oral Semaglutide (Rybelsus)
Rybelsus is the same active ingredient as Ozempic but taken as a daily pill instead of a weekly injection. It’s the only GLP-1 receptor agonist available in oral form. You take it on an empty stomach with a small sip of water, then wait at least 30 minutes before eating or drinking anything else, because food interferes with absorption.
The glucose-lowering and weight loss effects are similar to the injectable version, though the convenience of a pill appeals to people who want to avoid needles. Side effects mirror injectable semaglutide, with nausea being the most common early on.
4. Tirzepatide (Mounjaro)
Tirzepatide is a newer once-weekly injection that targets two gut hormones instead of one: GLP-1 and GIP. This dual action makes it particularly potent for both blood sugar reduction and weight loss. In clinical trials, tirzepatide produced some of the largest reductions in blood sugar and body weight seen with any diabetes medication. Cardiovascular outcome trials are still underway, so its heart benefits aren’t yet confirmed to the same degree as older GLP-1 drugs.
5. Empagliflozin (Jardiance)
Empagliflozin belongs to the SGLT2 inhibitor class. These drugs work in the kidneys, blocking a protein that normally reabsorbs sugar back into the bloodstream. The result: your body flushes excess glucose out through urine, lowering blood sugar without relying on insulin.
What sets Jardiance apart is its proven heart and kidney protection. In large clinical trials, it reduced the risk of cardiovascular death by 38% in people with type 2 diabetes and established heart disease. It also significantly reduced hospitalizations for heart failure. The main side effects are urinary tract infections and genital yeast infections, both related to the extra sugar passing through the urinary tract. Mild dehydration is also possible, so staying well-hydrated matters.
6. Dapagliflozin (Farxiga)
Farxiga is another SGLT2 inhibitor with a similar mechanism to Jardiance. Its standout feature is strong kidney protection. In one major trial, dapagliflozin reduced the risk of kidney disease progression, kidney failure, or death from kidney or cardiovascular causes by 39%. It’s now approved not just for diabetes but also for heart failure and chronic kidney disease on their own, even in people without diabetes. Side effects are the same as other SGLT2 inhibitors: increased urinary and genital infections.
7. Sitagliptin (Januvia)
Sitagliptin is a DPP-4 inhibitor, a class of once-daily pills that work by blocking an enzyme that normally breaks down incretin hormones. With more incretins circulating after a meal, your pancreas releases more insulin when blood sugar is high and less when it’s normal. This makes DPP-4 inhibitors relatively gentle: they carry a low risk of causing dangerously low blood sugar.
The trade-off is that they’re less powerful than GLP-1 agonists or SGLT2 inhibitors. They produce modest blood sugar reductions and little to no weight loss. They also lack the proven cardiovascular and kidney benefits of newer drug classes. Still, they’re well-tolerated and easy to take, which makes them useful for people who can’t tolerate or access other options.
8. Linagliptin (Tradjenta)
Linagliptin is another DPP-4 inhibitor with one practical advantage: it doesn’t require dose adjustment for people with kidney problems. Most diabetes medications need to be reduced or avoided when kidney function declines, but linagliptin is processed primarily through the gut rather than the kidneys. This makes it a common choice for older adults or anyone with moderate to severe kidney disease who needs a straightforward oral option.
9. Dulaglutide (Trulicity)
Trulicity is a once-weekly injectable GLP-1 receptor agonist that was one of the most prescribed diabetes medications in recent years. It lowers blood sugar effectively and produces moderate weight loss, though typically less than semaglutide or tirzepatide at their highest doses. It has proven cardiovascular benefits, reducing major cardiovascular events in people with type 2 diabetes. The injection comes in a pre-filled pen that’s straightforward to use, which helped make it popular among people new to injectables.
10. Insulin Glargine (Lantus, Basaglar, Semglee)
Insulin glargine is the most commonly used long-acting (basal) insulin. It begins working about two hours after injection, has no sharp peak, and provides a steady level of background insulin for up to 24 hours. It’s typically injected once daily, at the same time each day, and is often combined with oral medications or rapid-acting insulin taken before meals.
Insulin therapy becomes necessary when the pancreas can no longer produce enough insulin on its own, which happens as type 2 diabetes progresses, and is essential from the start for all people with type 1 diabetes. The main risks are low blood sugar (hypoglycemia) and weight gain. Biosimilar versions like Basaglar and Semglee have brought prices down compared to the original brand.
How These Medications Compare on Cost
The cost gap between diabetes drug classes is enormous. Generic metformin costs a few dollars per month. DPP-4 inhibitors and SGLT2 inhibitors fall in the middle, often $200 to $500 per month at list price, though insurance and coupons reduce this. GLP-1 receptor agonists and dual agonists like tirzepatide sit at the top, with U.S. list prices approaching $1,000 per month. A Yale School of Medicine analysis found these prices are drastically higher than actual production costs, which has fueled ongoing policy debates about drug pricing.
Your actual out-of-pocket cost depends heavily on your insurance plan, whether a generic or biosimilar exists, and whether you qualify for manufacturer savings programs. If cost is a barrier, it’s worth asking specifically about generic alternatives or patient assistance programs.
How Doctors Choose Between Them
The decision typically starts with metformin, then layers on additional medications based on your specific health profile. If you have heart disease or are at high risk for it, an SGLT2 inhibitor or GLP-1 agonist is usually added because of their proven cardiovascular benefits. If kidney disease is a concern, SGLT2 inhibitors have the strongest evidence for slowing progression. If weight loss is a major goal, GLP-1 agonists and tirzepatide offer the most significant results.
For people who need something simple, well-tolerated, and affordable, a DPP-4 inhibitor might be appropriate, even though it’s less powerful. And when blood sugar remains high despite multiple oral or injectable medications, insulin becomes part of the plan. Many people with type 2 diabetes end up on two or three medications from different classes, each targeting a different part of the problem.