There are six FDA-approved prescription medications for long-term weight management, ranging from daily pills to weekly injections. The newest injectable drugs produce dramatically more weight loss than older options, which is why they’ve dominated headlines, but the full landscape includes several different types of medications that work in distinct ways. Which one fits a given person depends on their health profile, how they feel about injections versus pills, and what they can access.
Who Qualifies for Weight Loss Medication
Prescription weight loss drugs are generally intended for adults with a BMI of 30 or higher (obesity) or a BMI of 27 or higher (overweight) who also have at least one weight-related health condition such as type 2 diabetes, high blood pressure, or high cholesterol. One exception is orlistat, which is available over the counter at a lower dose under the brand name Alli. The prescription options all require a doctor’s evaluation and ongoing monitoring.
The Weekly Injectables: Wegovy and Zepbound
The two most effective weight loss drugs right now are both weekly injections: semaglutide (Wegovy) and tirzepatide (Zepbound). They work by mimicking gut hormones that regulate appetite and blood sugar. When these hormones are active, you feel full sooner, stay satisfied longer, and experience fewer food cravings. The result is a significant and sustained reduction in how much you eat without the white-knuckle willpower that dieting typically requires.
Wegovy, approved in 2021, produces average weight loss of about 15% to 17% of body weight over one to two years. A higher-dose version showed roughly 21% weight loss at 72 weeks in clinical trials. For a 220-pound person, that translates to losing roughly 33 to 46 pounds.
Zepbound, approved in 2023, targets two gut hormones instead of one. In a head-to-head trial comparing the two drugs over 72 weeks, people on tirzepatide lost 20.2% of their body weight compared to 13.7% for those on semaglutide. That extra hormonal pathway appears to give Zepbound a meaningful edge in total weight lost, though both drugs outperform every other option on the market.
The Daily Injectable: Saxenda
Liraglutide (Saxenda) was the first GLP-1 drug approved specifically for weight loss. It works through the same appetite-suppressing mechanism as Wegovy but requires a daily injection rather than a weekly one, and it produces less weight loss overall. Most people lose around 5% to 10% of their body weight. Saxenda has largely been overshadowed by the newer weekly injectables, but it remains an option, particularly for people who want to start with a less potent drug or who can’t access the newer ones.
Oral Medications: Pills for Weight Loss
Three FDA-approved pills offer an alternative for people who prefer not to inject.
Phentermine-topiramate (Qsymia) is the most effective oral option. It combines an appetite suppressant with a drug originally used for seizures and migraines that also reduces hunger. In clinical trials, Qsymia had the highest odds of any medication for helping people reach at least 5% weight loss, with a number needed to treat of just 3. That means for every three people who take it, one achieves clinically meaningful weight loss who otherwise wouldn’t have. It’s taken once daily.
Naltrexone-bupropion (Contrave) pairs a drug used to treat alcohol and opioid dependence with an antidepressant. Together, they act on brain pathways that control hunger and cravings. The weight loss is moderate, similar to Qsymia, with a number needed to treat of 3 for 5% weight loss. Contrave tends to cause more side effects that lead people to stop taking it compared to other oral options. It’s taken once or twice daily.
Orlistat (Xenical or Alli) works completely differently from every other drug on this list. Instead of suppressing appetite, it blocks your body from absorbing about a third of the fat you eat. The unabsorbed fat passes through your digestive system, which is why greasy or oily stools are the drug’s signature side effect, especially after high-fat meals. Orlistat produces the most modest weight loss of any approved option. It’s taken three times daily with meals. The lower-dose version, Alli, is the only weight loss medication available without a prescription.
How the Injectables Feel Day to Day
The most common side effects of GLP-1 drugs are gastrointestinal: nausea, vomiting, diarrhea, and constipation. These tend to be worst during the first few weeks and during dose increases, then often improve as your body adjusts. The drugs are started at low doses and gradually increased over several weeks specifically to minimize these effects.
Less common but more serious complications include inflammation of the pancreas, slowed stomach emptying (sometimes severe enough that food barely moves out of the stomach), bowel obstruction, and gallstone attacks. Rapid weight loss from any cause can trigger gallstones, so this risk isn’t unique to the drugs themselves.
You may have heard of “Ozempic face,” a term for the hollowed, aged look that can develop when fat is lost quickly from the face. This can include sunken cheeks, more prominent wrinkles, and sagging along the jaw and neck. It’s not specific to any one drug. It happens with any rapid weight loss but has become closely associated with GLP-1 medications because of how much weight people lose on them.
Who Should Not Take These Drugs
GLP-1 drugs carry a specific warning related to thyroid cancer. In animal studies, these medications increased the risk of a rare type called medullary thyroid cancer. Because of this, people with a personal or family history of medullary thyroid cancer, or a rare genetic condition called multiple endocrine neoplasia syndrome type 2, should not use any GLP-1 or dual-agonist medication. This applies to Wegovy, Zepbound, and Saxenda alike.
People with a history of pancreatitis are also typically advised against these drugs. Pregnancy is another contraindication across all weight loss medications.
What Happens When You Stop
Weight regain after stopping medication is one of the biggest practical concerns. Studies consistently show that most people regain a significant portion of their lost weight within a year of discontinuing GLP-1 drugs. This is because the medications treat obesity the same way blood pressure pills treat hypertension: they manage the condition while you take them, but the underlying biology doesn’t change. Many people end up staying on these drugs indefinitely, which raises important questions about long-term cost and access.
What’s in the Pipeline
The next wave of weight loss drugs aims to push results even further. Retatrutide, currently in Phase 3 trials, targets three hormone receptors instead of two. In a Phase 2 obesity trial, the highest dose produced an average 24.2% reduction in body weight at 48 weeks, with weight still declining at the end of the study. A Phase 3 trial in people with type 2 diabetes showed average weight loss of about 37 pounds (16.8%) at 40 weeks, also without plateauing. Higher-dose oral versions of semaglutide (25 mg and 50 mg pills) are also in development, which could eventually give people injectable-level results from a daily pill.