"Feb. 1, 2012 -- We know we don't have a "magic bullet" yet when it comes to weight loss, but at least we can count on some old standbys -- like eating a little less each day adds up over time, breastfeeding means lean children, and when all else "...
(phentermine and topiramate) Extended Release Capsules
Qsymia capsule is a combination oral product comprised of immediate-release phentermine hydrochloride (as the free base) and extended-release topiramate. Qsymia contains phentermine hydrochloride, a sympathomimetic amine anorectic and topiramate, a sulfamate-substituted monosaccharide related to fructose antiepileptic drug.
The chemical name of phentermine hydrochloride is α,α-dimethylphenethylamine hydrochloride. The molecular formula is C10H15N • HCl and its molecular weight is 185.7 (hydrochloride salt) or 149.2 (free base). Phentermine hydrochloride is a white, odorless, hygroscopic, crystalline powder that is soluble in water, methanol and ethanol. Its structural formula is:
Topiramate is 2,3:4,5-di-O-isopropylidene-β-D-fructopyranose sulfamate. The molecular formula is C12H21NO8S and its molecular weight is 339.4. Topiramate is a white to off-white crystalline powder with a bitter taste. It is freely soluble in methanol and acetone, sparingly soluble in pH 9 to pH 12 aqueous solutions and slightly soluble in pH 1 to pH 8 aqueous solutions. Its structural formula is:
Qsymia is available in four dosage strengths:
- Qsymia 3.75 mg/23mg (phentermine 3.75 mg and topiramate 23 mg extended-release) capsules;
- Qsymia 7.5 mg/46 mg (phentermine 7.5 mg and topiramate 46 mg extended-release) capsules;
- Qsymia 11.25 mg/69 mg (phentermine 11.25 mg and topiramate 69 mg extended-release) capsules;
- Qsymia 15 mg/92 mg (phentermine 15 mg and topiramate 92 mg extended-release) capsules.
Each capsule contains the following inactive ingredients: methylcellulose, sucrose, starch, microcrystalline cellulose, ethylcellulose, povidone, gelatin, talc, titanium dioxide, FD&C Blue #1, FD&C Red #3, FD&C Yellow #5 and #6, and pharmaceutical black and white inks.
Last reviewed on RxList: 4/8/2013
This monograph has been modified to include the generic and brand name in many instances.
Additional Qsymia Information
- Qsymia Drug Interactions Center: phentermine-topiramate oral
- Qsymia Side Effects Center
- Qsymia FDA Approved Prescribing Information including Dosage
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Find out what women really need.