Does Phentermine increase libido? 

Does Phentermine increase libido? 

Phentermine may or may not increase libido. Some people have reported this side effect early in their treatment with Phentermine. It can increase sexual desire in both men and women and enhance mood and playfulness. 

This is usually a well-received side effect, but it can affect the quality of your life if it’s causing insomnia or any other side effect. However, in some cases, the exact opposite effects are observed. Some people lose their libido when they start the treatment. 

Some of the people who suffer from this side effect continue to feel this way as their treatment continues, whereas some people have reported that they first lost their libido, but then it increased. This indicates that Phentermine may affect libido differently in different people. 

What does research suggest?

There is limited research on the effects of Phentermine on libido. Phentermine is a medication primarily used for weight loss and appetite suppression. It is not specifically intended to increase libido or sexual desire. (1,2)

However, some studies suggest that Phentermine may have a positive impact on sexual function and desire in some individuals, possibly due to weight loss and increased self-confidence. However, other studies have not found a significant correlation between Phentermine use and changes in libido.

It’s important to note that medication effects can vary between individuals, and personal experiences may differ. If you have concerns about changes in libido while taking phentermine, it is recommended to discuss them with your healthcare provider. 

What to do if Phentermine-induced increased libido is affecting your daily life? 

If Phentermine continues to increase your libido and it starts to affect the quality of your life, talk to your healthcare provider. Side effects are expected to go away when your body adjusts to the medication. 

However, if they persist, you should consult your doctor, who’ll help you determine if it’s safe to continue using Phentermine. Your doctor may consider modifying your Phentermine dosage or exploring alternative medications to manage your weight loss goals while minimizing the impact on your libido.

You can also consider talking to a therapist who specializes in sexual health or relationship issues. They can provide guidance and strategies to cope with changes in libido and help you navigate any challenges it may be causing in your daily life.

Just make sure you take Phentermine in the best possible way to prevent as many side effects as possible. The drug may upset your stomach, which can be prevented by taking it with food – instead of taking it on an empty stomach

If you can’t tolerate how the medication makes you feel, please discuss it with your doctor. 

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Kim KK, Cho HJ, Kang HC, Youn BB, Lee KR. Effects on weight reduction and safety of short-term phentermine administration in Korean obese people. Yonsei Med J. 2006 Oct 31;47(5):614-25. doi: 10.3349/ymj.2006.47.5.614. PMID: 17066505; PMCID: PMC2687747.


Johnson DB, Quick J. Topiramate And Phentermine. 2023 Mar 27. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 29489234.