Qsymia
The United States brand name for a capsule combining phentermine and extended-release topiramate. An EU-wide authorisation was refused in 2013.
General information, not medical advice. Docalo does not sell medicines, and prescription-only medicines are prescribed only after an individual medical assessment.
What Qsymia is and how it works
Qsymia combines phentermine, an appetite suppressant, with topiramate, an epilepsy and migraine medicine that also reduces how much people want to eat.
In 2013 the EMA's committee refused an EU-wide authorisation for the same combination, then called Qsiva, citing concerns about long-term effects on the heart and circulation, on mental health and in pregnancy. Sweden later authorised it nationally through a decentralised procedure finalised in 2020.
Authorisation status and label
- In the United States, Qsymia is labelled for chronic weight management in adults with obesity, or overweight with a weight-related condition, and in children aged 12 and over with obesity.
- It is used alongside a reduced-calorie diet and increased physical activity.
- It holds no EU-wide authorisation; a few European countries authorise it nationally under the name Qsiva.
Only a doctor who knows your history can decide whether a medicine suits you.
How to use Qsymia
Once a day, in the morning. The US label describes one capsule each morning; taking it in the evening can cause trouble sleeping.
Built up in steps. The US label starts at 3.75 mg/23 mg for 14 days, then 7.5 mg/46 mg. Higher doses, up to 15 mg/92 mg, follow only after review.
Stopped gradually. Stopping from the highest dose is gradual, with a dose every other day for at least a week, because stopping topiramate abruptly can trigger seizures.
Common side effects
Get urgent medical help if (whatever the frequency): Sudden eye pain, redness or blurred vision, Thoughts of harming yourself, or a sudden change in mood, A racing or irregular heartbeat, or chest pain
Most reported in trials (in more than 1 in 10 trial participants): dry mouth, pins and needles, constipation
Also reported in trials (less often): dizziness, trouble sleeping, changes in taste, low mood or anxiety
Safety
Do not use Qsymia if
- You are pregnant: topiramate can cause birth defects, so a negative pregnancy test is needed before starting and every month
- You have glaucoma or an overactive thyroid
- You have taken an MAO inhibitor in the last 14 days
- You have ever had an allergic reaction to phentermine, topiramate or similar stimulant medicines
Phentermine raises heart rate, and topiramate can affect mood and concentration. Reliable contraception is required throughout treatment.
Your questions answered
Is Qsymia authorised in the EU?
Why is a pregnancy test needed?
More questions
Can Qsymia be stopped suddenly?
References
This page summarises the official product information and the published sources below.
- Qsiva: refusal of marketing authorisation (EMEA/H/C/002350) European Medicines Agency, 2013
- Questions and answers on the refusal of the marketing authorisation for Qsiva (phentermine / topiramate) European Medicines Agency, 2013
- Qsiva Public Assessment Report, decentralised procedure SE/H/1963/01-04/DC Swedish Medical Products Agency, 2020
- Qsymia (phentermine / topiramate extended-release): US prescribing information US Food and Drug Administration, 2024
- Effects of low-dose, controlled-release phentermine plus topiramate on weight and associated comorbidities (CONQUER). Lancet 2011;377:1341-52 The Lancet, 2011
Other medicines used in weight management
Talk to a doctor about weight care
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Talk to a doctor about weight careGeneral information, not medical advice. Docalo does not sell medicines, and prescription-only medicines are prescribed only after an individual medical assessment.
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