The Best Appetite Suppressants in 2024: A Comprehensive Review

Losing weight and sustaining weight loss are notoriously difficult. If you’re struggling to reach your weight goals, you might consider taking an appetite suppressant to aid with appetite control.

Appetite suppressants are medications or supplements that dull your desire to eat. Although they can be effective, they’re not meant to be magical weight loss pills. To get the best results, they should be combined with regular exercise and a reduced calorie diet.

Your doctor may recommend taking these medications if you have obesity  or overweight, but it’s also important to talk to your doctor before taking weight loss supplements since many products marketed for weight loss aren’t known to be safe or effective.

Keep reading to learn about prescription and over-the-counter appetite suppressants that may help with weight loss and support your overall wellness. We’ll also explore some dietary strategies for reducing appetite.

GLP-1 receptor agonists are a group of medications often used to aid with weight loss or help people with type 2 diabetes control their blood sugar.

GLP-1 agonists work by mimicking a hormone produced by your digestive tract called GLP-1. This hormone is one of your body’s incretin hormones, which act on your pancreas to increase insulin production and decrease glucagon production.

Insulin lowers blood sugar levels while glucagon raises it.

Insulin produced by GLP-1 agonists also acts directly on your brain to stimulate a feeling of fullness and slow the passage of food through your stomach.

Semaglutide

The medication semaglutide is Food and Drug Administration (FDA)-approved to aid with weight loss for people who are overweight or obese and improve blood sugar control for people with type 2 diabetes.

Semaglutide is not currently available as a generic drug in the United States, but it’s sold under three brand names.

• Ozempic® is available as a subcutaneous injection. It’s FDA-approved to aid with type 2 diabetes blood sugar control in combination with regular exercise and a healthy diet.

• Rybelsus® is available in oral tablets. It’s also FDA-approved to aid with type 2 diabetes blood sugar control in combination with regular exercise and a healthy diet.

• Wegovy® is available as a subcutaneous injection. It’s FDA-approved to aid with weight loss for people who have obesity or overweight with weight-related complications such as high blood pressure or high cholesterol.

Additionally, semaglutide is available as a compounded medication since Wegovy and Ozempic appear on the FDA’s shortage list.

Compounded medications are custom-made medications often produced by licensed pharmacists that offer the same active ingredient as brand-name alternatives. Compounded medications, such as Hers semaglutide, are often sold at a cheaper price than brand-name alternatives. Compounded medications are not FDA approved.

Who’s Eligible for Semaglutide?

Wegovy is FDA-approved for people who have obesity or people who are overweight with at least one weight-related complication.

• Obesity is defined as a body mass index (BMI) over 30.

• Overweight is defined as a BMI over 27.

(Our BMI calculator can show you where yours falls.)

Ozempic and Rybelsus are FDA-approved for people with diabetes, but they’re frequently prescribed off-label for those working on weight loss. Off-label is when a doctor prescribes a medication for a condition other than the condition it’s been approved to treat.

When Ozempic or Rybelsus are prescribed off-label, doctors often follow the same eligibility requirements as Wegovy.

Semaglutide Effectiveness

Semaglutide can potentially suppress your appetite and make you feel more full. Many people who take semaglutide are able to lose a significant amount of weight. For best results, it’s important to combine semaglutide with a healthy diet and regular exercise.

Many people who take semaglutide find they experience less “food noise,” which is a relatively new term that refers to intrusive thoughts about food or eating throughout the day.

In a 2021 study published in the highly respected New England Journal of Medicine, researchers compared the effectiveness of semaglutide injections to a placebo for aiding weight loss over 68 weeks.

The researchers recruited almost 2,000 people with a BMI over 30 or a BMI over 27 with at least one weight-related complication.

People in the placebo group lost an average of 2.6 kilograms (around 5.7 pounds) compared to 15.3 kilograms (about 33.7 pounds) for people in the semaglutide group. This corresponded to 14.9% body weight in the semaglutide group and 2.4% body weight in the placebo group.

Semaglutide Side Effects and Considerations

All appetite suppressant pills and injections have a potential for side effects. The most common side effects of semaglutide reported in clinical trials are mostly gastrointestinal (GI). They include:

• nausea

• constipation

• diarrhea

• vomiting

• abdominal pain

• headaches

• fatigue

• upset stomach

• dizziness

• abdominal bloating

• burping

• gas

Additionally, the FDA includes a black box warning on the label of semaglutide products indicating that semaglutide has been linked to thyroid cancer in rodents. A black box warning is the highest safety-related warning the FDA administers.

It’s unknown if semaglutide could cause thyroid cancer in humans. To be cautious, it’s not recommended for people with a family history of multiple endocrine neoplasia syndrome type 2 or medullary thyroid carcinoma.

Liraglutide

Liraglutide has a similar action in your body as semaglutide since they’re both GLP-1 agonists. The FDA first approved liraglutide for weight loss in 2020. It’s also approved to help with type 2 diabetes blood sugar control.

In the United States, liraglutide is available as a generic drug as well as under three brand names.

• Victoza® is FDA-approved to aid with type 2 diabetes blood sugar control along with a balanced diet and regular exercise. It’s also approved to reduce the risk of serious cardiovascular events in people with type 2 diabetes.

• Saxenda® is FDA-approved for obesity treatment in people who have a BMI over 30 or a BMI over 27 with at least one weight-related complication.

• XULTOPHY® 100/3.6 is a combination of liraglutide and synthetic insulin. It’s FDA-approved to treat type 2 diabetes not controlled adequately with either of these medications alone.

Liraglutide Effectiveness

Three clinical trials that led to the approval of Saxenda compared weight loss on liraglutide to weight loss on a placebo over 56 weeks. These trials reported the following:

Liraglutide Side Effects and Considerations

The most common side effects of liraglutide reported in clinical trials include:

• headache

• nausea

• diarrhea

• immune response against liraglutide

• hives and other allergic symptoms

Liraglutide gets the same black box warning about the potential to increase the risk of thyroid cancer as semaglutide.

Liraglutide vs. Semaglutide

Liraglutide has a shorter half-life than semaglutide, meaning it doesn’t act as long in the body. It’s administered as a daily injection as opposed to a weekly injection.

In a 2022 clinical trial, researchers found that semaglutide and liraglutide both led to weight loss in adults, but that semaglutide led to more weight loss.

Semaglutide led to an average of 15.8% loss of body weight over 68 weeks compared to 6.4% with liraglutide.

In the United States, Naltrexone-bupropion is an oral medication sold under the brand name Contrave®. It’s a combination of two medications that act on your hypothalamus and other parts of your brain that control satiety and reduce your appetite:

• Naltrexone, an opioid antagonist

• Bupropion, an aminoketone antidepressant

Contrave is FDA-approved for obesity treatment in people with a BMI over 30 or over 27 with at least one weight-related complication.

Clinical trials that led to the approval of Contrave and lasted over a year reported weight loss percentages ranging from 3.7% to 8.1%.

Naltrexone-bupropion Side Effects and Considerations

Side effects of Contrave can include:

• nausea

• constipation

• headaches

• vomiting

• dizziness

• insomnia

• dry mouth

• diarrhea

The FDA includes a black box warning for an increased risk of suicidal thinking in children, adolescents, and young adults also taking anti-depressants for major depressive disorder or other psychiatric disorders.

The oral medication phentermine-topiramate is sold under the name Qsymia® in the United States and can act as a strong appetite suppressant. This medication is a combination of two medications that act on your brain:

• Phentermine, which helps reduce your appetite

• Topiramate, which makes you feel full

Qsymia is FDA-approved for obesity management in adults with a BMI over 30 or with a BMI over 27 with at least one weight-related complication. It’s also approved for children over 12 above the 95% percentile of body weight for their age and sex.

Year-long clinical trials that led to the approval of Qsymia reported weight loss of 3.5% to 9.4% compared to a placebo depending on the dose.

Phentermine-topiramate Side Effects and Considerations

The FDA does not include a black box warning for this medication. The most common side effects in adults are:

• pins and needles sensation

• dizziness

• changes in your taste

• insomnia

• constipation

• dry mouth

In children, the most commonly reported side effects are:

• depression

• dizziness

• joint stiffness

• fever

• influenza

• ligament sprains

Orlistat is an oral medication sold under the brand names Xenical® and Alli® in the United States. Unlike some medications that directly act on your hypothalamus to reduce your appetite, it increases fullness by binding to your digestive enzymes and inhibiting fat absorption by about 30%.

It’s FDA-approved to reduce obesity in combination with a reduced-calorie diet. It’s also approved to help reduce weight regain after weight loss.

Year-long clinical trials have found that 16.4% to 22.8% of people lost more than 10% of their body weight while taking Orlistat compared to 6.5% to 11.9% of people taking a placebo. The results of 2-year studies are similar.

Orlistat Side Effects and Considerations

The most commonly reported side effects in people taking orlistat include:

• gas with discharge

• frequent or urgent need to pass stool

• fatty or oily stools

• fecal incontinence

Setmelanotide is sold under the name Imcivree® in the United States. It’s an injection that acts on melanocortin-4 receptors in your hypothalamus to make you feel more full.

It’s FDA-approved to treat obesity caused by the following genetic conditions:

• pro-opiomelanocortin

• proprotein convertase subtilisin/kexin type 1

• leptin receptor deficiency

• Bardet-Biedl syndrome

It can be effective for weight loss in people with these genetic conditions but hasn’t been evaluated or approved for the general population.

Metformin is the first-line treatment for treating type 2 diabetes. It’s administered orally  and is currently the only medication recommended by the American Diabetes Association for treating prediabetes. It works by:

• lowering blood sugar production in the liver

• diminishing intestinal absorption of blood sugar

• enhancing insulin sensitivity

Although it’s primarily used for treating type 2 diabetes, it has also been used off-label for:

• managing pregnancy-induced (aka gestational) diabetes

• addressing weight gain caused by antipsychotic medications

• preventing type 2 diabetes

• treating and preventing polycystic ovary syndrome

Metformin’s ability to lower blood sugar levels can also potentially help with appetite suppression when insulin acts on a part of your brain called the hypothalamus.

The weight loss effects of metformin are usually modest compared to other medications. However, weight loss can be a beneficial side effect when taking metformin to help control your type 2 diabetes.

Metformin Side Effects and Considerations

Up to 30% of people using metformin develop GI side effects such as:

• diarrhea

• vomiting

• nausea

Less common side effects include:

• chest pain

• headaches

• abnormal sweating

• low blood sugar

• weakness

• nasal congestion

• decreased vitamin B12 with prolonged use

It also comes with a black box warning for a serious condition called lactic acidosis, which occurs in about 1 in 30,000 people. This condition can be life-threatening.

The following medications can potentially help with weight loss but are meant to be taken short-term by people who can't lose weight with exercise and a healthy diet alone. They have the potential to be addictive.

• Benzphetamine acts on your hypothalamus to decrease your appetite. It’s generally only prescribed for a few weeks since it can be addictive and you build a tolerance.

• Diethylpropion is generally approved for up to 12 weeks. It can aid weight loss by stimulating your central nervous system.

• Phendimetrazine also works by stimulating your central nervous system to reduce your appetite.

• Phentermine can aid weight loss by suppressing your appetite when combined with exercise and a healthy diet. It’s only FDA approved for up to 12 weeks.

In addition to prescription options, many dietary supplements available over-the-counter have appetite-suppressing properties.

The FDA doesn’t approve dietary supplements, though. It’s a good idea to talk to your doctor before taking supplements for weight loss.

Some products advertised as natural appetite suppressants contain ingredients that aren’t effective or potentially harmful:

• Garcinia Cambogia contains the active ingredient hydroxycitric acid (HCA). HCA may increase serotonin levels to reduce your appetite. Research on its effectiveness for body fat loss is mixed.

• Green tea extract contains catechins and caffeine. These chemicals may help reduce your appetite and increase fat burning by stimulating your metabolism.

• Glucomannan is a dietary fiber from the root of the konjac plant. It absorbs water in the stomach, expanding to create a feeling of fullness. Research on its effectiveness is mixed, but some reviews have found a potential benefit.

• Cayenne pepper contains a group of chemicals called capsaicinoids. These chemicals may dull your appetite and increase your metabolism.

There’s no such thing as a miracle weight loss pill. All medications designed to dull your appetite are best combined with a balanced diet and regular exercise.

The soluble fiber found in many foods is a safe appetite suppressant in itself as it can help prevent overeating. These foods include:

• beans

• Brussels sprouts

• sweet potatoes

• broccoli

• carrots

• pears

• figs

• apricots

• apples

• flax seed

• oats

• barley

Other dietary and lifestyle habits that can support your weight management efforts include:

• eating plenty of protein

• drinking plenty of water and fluids

• eating more natural foods and fewer ultra-processed foods

• choosing solid foods versus getting most of your calories from liquids

• eating slowly and chewing your food thoroughly

• getting adequate sleep

• reducing stress

There are several weight loss medications out there that can help you suppress your appetite, including popular options like semaglutide, liraglutide, and metformin. Of course, the effectiveness varies, and you may have to meet certain criteria to get a prescription.

As with other weight loss methods, having a calorie deficit is crucial. Appetite suppressants can help reduce the number of calories you take in, but for best results, they should be combined with regular exercise, a balanced diet, plenty of water, and adequate sleep.

All medications have the potential to cause side effects, and some diet pills or injections aren’t suitable for people with certain underlying health conditions. Remember: OTC options aren’t vetted by the FDA. Some actually do more harm than good.

If you’re thinking about taking an appetite suppressant, consult a healthcare provider that can help you decide if appetite suppressants might be right for you and which type to try.