What is the strongest weight loss prescription pill?

What is the strongest prescription pill for weight loss?

For this article, we define “strongest” as the medication associated with the highest percentage of body weight loss. Phentermine-topiramate (Qsymia) is a combination medication that’s considered one of the most effective prescription weight loss pills. Phentermine is a stimulant that has traditionally been used as a weight loss medication, and topiramate is used to treat seizures.

Phentermine-topiramate can help people lose 8% to 10% of their body weight over one year.

In 2012, the Food and Drug Administration (FDA) approved the combination for adults with a body mass index (BMI) of 30 or a BMI of 27 with at least one weight-related health condition, such as high blood pressure or type 2 diabetes.

How does phentermine-topiramate work?

The phentermine part of the medication helps address hunger, while the topiramate part helps reduce cravings, according to Dr. Brianna Johnson-Rabbett, an obesity medicine physician and endocrinologist at Nebraska Medicine. "Especially in combination, this can assist as a tool to help change what we eat and drink in a way that supports weight loss,” she said.

People taking phentermine-topiramate can lose between 8% to 10% of their body weight over the span of a year, according to Thomas So, a senior manager of the consumer drug information group at First Databank, which provides drug information to health care providers. One study reports, at the maximum dose, up to an 11% weight loss after a year of being on the medication.

For context, naltrexone-bupropion (Contrave), another prescription weight loss combination pill, averages 5% to 9% weight loss, and over-the-counter oral medication orlistat (sold under the brand name Alli) averages weight loss between just 3% and 5%, according to So. On the other hand, tirzepatide (an injectable) boasts an over 20% body weight loss at the highest dose.

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What are the side effects of weight loss prescription pills?

Like any medication, the potential for side effects of weight loss pills needs to be monitored. Each of these medications has multiple doses available, and a health care provider is trained on whether dose adjustments should be made depending on how your body responds.

Most common side effects of phentermine-topiramate

Phentermine-topiramate side effects may be unpleasant, but many can be managed or alleviated.

• Dry mouth: Dry mouth can happen when initially starting medication but can get better as your body adjusts.
• Trouble sleeping: If you’re having trouble sleeping, you might take your dose in the morning, especially during the first few weeks of beginning phentermine-topiramate.
• Constipation: Constipation may continue long-term as long as you're on medication. Increasing your dietary fiber, drinking plenty of water or taking a mild laxative can help.
• Dizziness: Dizziness, along with numbness or tingling are usually temporary side effects as well and may happen as your dose increases.

More serious phentermine-topiramate side effects

Phentermine-topiramate is considered a controlled substance, and it’s possible to become dependent on it. However, when used under a doctor’s supervision for weight loss, that risk is relatively low. It can also cause mental health changes, so let your doctor know if you’re experiencing any concerns with your mood. Inform your health care provider or get help right away if you're experiencing symptoms such as:

• Feeling like your heart is racing or pounding and lasts more than a few minutes
• Vision difficulties
• Pain or redness in the eye
• Numbness or tingling in the hands or feet
• Rapid breathing
• Severe back or side pain
• Blood in the urine
• Rash, hives, peeling or blistering skin
• Irritability, depression, anxiety or thoughts of suicide

Can you take weight loss medications long-term?

Generally, weight loss pills are safe to take long-term when used under your health care provider’s supervision. Studies in patients taking phentermine-topiramate for over two years have been performed.

Don’t take weight loss medications if you're trying to get pregnant, currently pregnant or breastfeeding.

“Obesity should be considered a chronic condition and may need long-term management,” So explained. “Stopping prescription pills for weight loss can often lead to regaining the lost weight, while long-term weight loss can help to lower the risk of heart disease, diabetes and improve quality of life.”

What are the alternatives to prescription weight loss pills?

One effective over-the-counter weight loss aid that’s FDA-approved is orlistat (Alli), which is a 60-milligram dose that you take up to three times a day with fat-containing meals. A higher dose (120 milligrams) of orlistat is also available, but it’s by prescription only. Orlistat works by blocking a portion of dietary fat that’s absorbed in your intestine. Studies have shown about 2% to 3% greater total body weight loss with orlistat over a placebo, Johnson-Rabbett said.

Nonprescription alternatives to weight loss pills

Plenty of OTC weight loss supplements, including caffeine, green tea extract, apple cider vinegar and berberine, are available. But our experts agree — few studies support their effectiveness and safety. It’s possible to lose one to seven pounds on these supplements, according to So.

Acupuncture (a component of traditional Chinese medicine that involves a trained practitioner inserting tiny needles into the skin) may be another option. A 2018 study showed it could be used effectively for weight loss, and another analysis found acupuncture can decrease your waist circumference and BMI when used along with lifestyle changes.

Any weight loss plan works best when it’s used along with lifestyle changes. But these methods can also be effective without taking weight loss medication. According to So, these include:

• Eating a nutritious diet: Make small changes that you can stick with.
• Getting regular physical activity: Aim for at least 150 minutes a week and include strength training twice a week.
• Incorporating better sleep habits: Try to get seven to nine hours of sleep a night, have a regular bedtime and limit screen time before bed.
• Managing your stress levels: Practice healthy coping techniques, such as journaling, walking or pursuing hobbies.
• Supporting mental health needs: Consider working with a therapist, personal trainer, nutritionist or dietitian if you find stress or emotions are a source of weight gain.

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How to choose the right weight-loss prescription pill

Health care providers consider different factors when creating a treatment plan for weight loss management. First, you’ll start out with an evaluation of your health and medication history, your health goals and any symptoms you might be having, such as symptoms of type 2 diabetes, liver disease or sleep apnea — health conditions that are associated with obesity.

Your provider will also ask about your daily life, including home and work responsibilities, sleep and dietary patterns and your physical activity, Johnson-Rabbett explained. Some weight loss medications may not be safe for you to take, so your provider will weigh the risks and benefits with you on the different types of weight loss medications while also providing you with alternative treatment options. Since insurance may or may not cover some or all weight loss medications, financial cost is also a factor to consider.

“Given the complexity of this process, it is important to work with a physician or provider competent in obesity medicine care when attempting to select the right medication for you,” Johnson-Rabbett said. She added that each person needs a personalized approach to weight management since every person and their weight loss goals are different.

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