Can you take phentermine and semaglutide together for weight loss?

If you’ve been on weight loss medication and haven’t seen your desired results, you may be thinking, “Can you take phentermine and semaglutide together?” This article uncovers the potential reasons why you may want to consider taking these 2 weight loss medications at the same time.

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If you struggle to manage your weight, ask your provider about the combination of phentermine and semaglutide. Find a provider for weight loss treatment on Klarity Health today and explore the options available to you.  

Yes, you can take phentermine and semaglutide together

Phentermine and semaglutide promote weight loss in different ways. Since there are no documented interactions between the 2 medications, you can take them together with your provider’s supervision.

While no large clinical trials have been done on the effects of combining semaglutide and phentermine, case reports have shown that the addition of semaglutide to weight loss medication (including phentermine) increased weight loss after a 1-year plateau. 

More research is needed to understand the potential long-term risks of taking them together to lose weight. 

It’s best to work with your weight loss provider to determine the right treatment for you. 

Why take phentermine and semaglutide together for weight loss

When used together, phentermine and semaglutide have complementary effects. The 2 together may help you lose more weight than either medication alone.

Phentermine suppresses appetite and reduces hunger pangs, while semaglutide controls blood sugar levels and promotes weight loss by making you feel fuller longer, so you eat less.

Anecdotal evidence suggests that phentermine may help combat the fatigue that can happen on semaglutide — especially when you start taking it. 

Potential weight loss on phentermine and semaglutide

A retrospective cohort study, found that 4,340 out of 7,043 (62%) of patients taking phentermine for short-term use experienced at least 3% weight loss in 3 months. 

Another found that individuals lost between 5 to 10% of their body weight in 12 weeks on Qsymia (phentermine-topiramate) over a 56-week period. 

Studies have also shown that with diet and exercise changes, clinical trial participants lost an average of 14.9% of their body weight over 68 weeks on Wegovy (semaglutide). 

Adding a short-term medication like phentermine to an already existing weight-loss regimen could help you lose more weight. 

Why not take semaglutide and phentermine together

Combining semaglutide and phentermine can increase the chance of experiencing side effects, especially if you have blood sugar issues or diabetes. While the drugs don’t have any known interactions with each other, they can affect the way your body reacts to alcohol and other medications.

It’s potentially dangerous to combine phentermine with alcohol as it can increase the risk of cardiac complications like chest pain, a rapid heart rate, and blood pressure changes. And because phentermine is a central nervous system (CNS) stimulant, it may not be suitable for those with high blood pressure, agitated states, or a history of hyperthyroidism. 

Phentermine shouldn’t be taken if you’re currently or have recently been on a monoamine oxidase inhibitor (MAOI), as it may cause hypertension or a serious, life-threatening condition known as serotonin syndrome. 

Semaglutide has the potential to affect how other orally taken medications are absorbed in the body and can influence how well and how quickly they work.

What you need to know about semaglutide and phentermine 

Because semaglutide lowers blood sugar, use it and phentermine together with caution.

Phentermine’s boxed warning cautions users that it may interact with hypoglycemic medications like insulin or oral diabetes medications. Semaglutide was originally approved as Ozempic to treat type 2 diabetes.

This means that if your healthcare provider prescribes the combination of semaglutide and phentermine, you may need to check your blood sugar levels more frequently and adjust your diabetes medications more often.

What is semaglutide?

Semaglutide belongs to the glucagon-like peptide-1 (GLP-1) agonist class. It activates receptors in the brain that help control appetite and food intake, leading to weight loss. 

It was originally FDA-approved as Ozempic in 2017 to treat adults with type 2 diabetes. In 2021, it was approved as Wegovy for chronic weight management. 

It is available by prescription in a compounded semaglutide formulation and sold under the brand names Wegovy, Rybelsus, and Ozempic. Wegovy and Ozempic are injections taken once a week. Rybelsus is an oral tablet taken every day.

What is phentermine?

Phentermine is a Schedule IV controlled substance and sympathomimetic amine that was FDA-approved in 1959 as an appetite suppressant. It affects the central nervous system, reduces hunger and boosts energy expenditure to produce weight loss. 

Phentermine is only available by prescription and can be found as a generic or under the brand names Acxion, Adipex, Adipex-P, Duromine, Elvenir, Fastin, Ionamin, Lomaira, Panbesy, Razin, Redusa, Sentis, Suprenza, and Terfamex.

Possible side effects of phentermine and semaglutide

Taking these medications individually or in combination may lead to potential side effects. If you plan to use them together, here’s what you should know.

Phentermine’s boxed warning cautions users that it may interact with hypoglycemic medications like insulin or oral diabetes medications. Individuals with diabetes or those taking other medications that can lower blood sugar should be particularly cautious if taking phentermine and semaglutide together.

In its boxed warning, semaglutide warns that it should not be used in patients with medullary thyroid cancer (MTC) or MEN 2 syndrome as it has been shown to induce tumor growth in rodents. 

Semaglutide shouldn’t be taken along with insulin without your doctor’s supervision.

Common phentermine side effects

• Increased heart rate
• Chest pain
• Changes in blood pressure
• Heart palpitations
• Dizziness
• Difficulty sleeping
• Swelling of the lower extremities

Learn more about phentermine side effects in women.

Common semaglutide side effects 

• Hypoglycemia
• Headache
• Dizziness
• Tremor
• Nausea
• Weakness
• Heart palpitations
• Rapid heartbeat 

Learn more about Ozempic side effects and Wegovy side effects. 

Alternatives to taking phentermine and semaglutide together

Alternatives to semaglutide include medications like liraglutide (sold as Saxenda) or tirzepatide (sold as Zepbound and Mounjaro). As an alternative to phentermine, the combination of phentermine and topiramate, sold as Qsymia, may be a suitable option. Contrave (naltrexone HCL/bupropion HCL) and Xenical (orlistat) are also popular weight-loss medications. Learn more about the best weight loss pills and injections. 

Key takeaways

• It’s possible to take phentermine and semaglutide together since they work differently to promote weight loss.
• Harnessing phentermine’s appetite suppression and semaglutide’s ability to promote a feeling of fullness may enhance overall weight loss outcomes.
• Semaglutide and phentermine treatment could lower blood sugar, so it may be necessary to monitor your blood sugar closely during treatment.

Talk to a provider about weight loss today

Reach out to a weight-loss specialist today to get the support you need to achieve and maintain your ideal weight. Find a provider on Klarity Health to get started.