What are the available dose forms of Qsymia (phentermine/topiramate)?

Available Dose Forms of Qsymia

Qsymia (phentermine/topiramate ER) is available in four capsule dose forms: 3.75/23 mg, 7.5/46 mg, 11.25/69 mg, and 15/92 mg, which are designed to be taken once daily in the morning as part of a gradual dose escalation regimen. 1

Dose Forms and Administration

• Qsymia is available exclusively as extended-release (ER) capsules in four different strengths 1:

  • 3.75 mg phentermine/23 mg topiramate
  • 7.5 mg phentermine/46 mg topiramate
  • 11.25 mg phentermine/69 mg topiramate
  • 15 mg phentermine/92 mg topiramate

• Qsymia is designed to be taken once daily in the morning, following a specific dose escalation schedule 1

Dosing Schedule and Titration

• The recommended dose titration follows this schedule 1:

  • Initial dose: 3.75/23 mg daily for 14 days
  • Then increase to: 7.5/46 mg daily
  • At 12 weeks, evaluate effectiveness and consider further titration if needed:
    • Option to increase to 11.25/69 mg daily for 14 days
    • Then potentially increase to 15/92 mg daily (maximum dose)

• The medication should be discontinued or the dose escalated if 3% weight loss is not achieved after 12 weeks at the 7.5/46 mg daily dose 1

• Treatment should be discontinued if 5% weight loss is not achieved after 12 weeks at the maximum 15/92 mg daily dose 1

Clinical Considerations

• Qsymia was the first combination medication for chronic weight management approved by the FDA in 2012 1

• The fixed-dose combination targets different mechanisms simultaneously for an additive effect on weight loss, addressing the complex nature of obesity 1

• In clinical trials, Qsymia demonstrated significant weight loss compared to placebo:

  • 7.5/46 mg daily dose: 7.8% weight loss at 1 year 1
  • 15/92 mg daily dose: 9.8% weight loss at 1 year 1

• Common side effects include paresthesia, dizziness, dysgeusia, insomnia, constipation, and dry mouth 1

• Qsymia is contraindicated during pregnancy due to the risk of fetal malformations (particularly cleft lip/palate) associated with topiramate 1

• As a Schedule IV controlled substance, Qsymia should not be prescribed to patients with cardiovascular disease, hyperthyroidism, glaucoma, or those taking monoamine oxidase inhibitors 1

Practical Prescribing Tips

• Gradual dose escalation helps minimize risks and adverse events 1

• Qsymia should be taken once daily in the morning, not in divided doses 1

• Regular monitoring is recommended at least monthly for the first 3 months and then at least every 3 months thereafter 1

• Women of childbearing potential must use effective contraception while taking Qsymia due to teratogenic risks 1