Phentermine/Topiramate

About Phentermine/Topiramate

Phentermine, a sympathomimetic amine, is thought to reduce appetite by releasing catecholamines in the hypothalamus; topiramate may curb appetite and increase the feeling of fullness, though exactly how either drug causes weight loss is not known. With a reduced-calorie diet and more physical activity, the capsule is approved for adults and children 12 and older with obesity, and for adults with overweight and at least one weight-related condition; its effect on heart disease and death has not been established. It is taken each morning, since an evening dose can cause insomnia: 3.75/23 mg for 14 days, then 7.5/46 mg. After 12 weeks on that dose, an adult who has not lost at least 3 percent of starting weight moves to 11.25/69 mg for 14 days, then 15/92 mg; if 12 weeks on 15/92 mg bring less than 5 percent, it is stopped. Children are judged by the change in BMI, and a lower dose is considered if they lose more than 2 pounds a week. Moderate or severe kidney impairment, or moderate liver impairment, caps the dose at 7.5/46 mg.

There is no boxed warning. It must not be taken in pregnancy, with glaucoma or an overactive thyroid, or within 14 days of an MAO inhibitor. Topiramate taken early in pregnancy raises the risk of major birth defects, including cleft lip and cleft palate, so a negative pregnancy test is recommended before starting and every month, with effective birth control throughout. Other warnings cover suicidal thoughts, sudden nearsightedness with a form of glaucoma and other vision problems, mood and sleep problems, cognitive impairment, slowed growth in children, metabolic acidosis, reduced kidney function, kidney stones, decreased sweating and overheating, low potassium, serious skin and allergic reactions, and allergy to an inactive ingredient, FD&C Yellow No. 5. Bicarbonate, creatinine and potassium are checked before starting and during treatment. Tingling, dizziness, altered taste, insomnia, constipation and dry mouth are the most common side effects in adults.

As a Schedule IV drug, a prescription can carry up to five refills within six months of the date written, and refill information can move to another pharmacy only once unless the pharmacies share a real-time online database. Because of the birth defect risk, Qsymia is available only through a limited program, the Qsymia REMS, under which only certified pharmacies may distribute it; a generic label names its own Phentermine and Topiramate Extended-Release Capsules REMS, with the same rule. Stopping topiramate abruptly has been linked to seizures, so the 15/92 mg dose is taken every other day for at least a week before stopping. Breastfeeding is not recommended.

Taking Phentermine/Topiramate

How to take it

Once a day in the morning, with or without food, at about the same time each day; an evening dose can cause trouble sleeping. Drink plenty of fluids, which helps prevent kidney stones, and take care in hot weather, since it can reduce sweating.

If you miss a dose

Skip the missed dose and take your usual dose the next morning. Do not take a double dose.

Storage

In the original container, tightly closed, at room temperature away from heat and moisture, out of reach of children. Use a take-back program rather than flushing it.

Interactions to know about

MAO inhibitors are not taken within 14 days. Alcohol and other sedating medicines add to dizziness and drowsiness, so do not drive until you know how it affects you. Other carbonic anhydrase inhibitors are avoided, and diuretics that lower potassium and valproic acid need monitoring. Spotting can occur with a combined birth control pill; do not stop the pill if it does.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Phentermine/Topiramate differs from pharmacy to pharmacy

Only pharmacies certified in a REMS program may distribute it, so fewer pharmacies can quote. Generic capsules come from only a few makers, so quotes spread more than for older generics, and a prescription that names Qsymia and blocks substitution is priced as a brand.

Starting treatment means short fills: 14 days of the starter strength, then the 7.5/46 mg capsules, and 14 days of 11.25/69 mg if the dose is raised, each with its own dispensing fee. Schedule IV refill information can usually be transferred only once, so it is worth choosing the pharmacy before the first fill.

Ways to pay less for Phentermine/Topiramate without insurance

• Ask for generic phentermine and topiramate capsules, and make sure the prescription allows substitution.
• Before sending the prescription, ask whether the pharmacy is certified in the REMS program for the product it would supply.
• Once your dose is steady, compare quotes from more than one certified pharmacy.
• If the brand is prescribed, ask the maker whether a savings program applies to someone paying cash; many copay cards require commercial insurance.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Phentermine/Topiramate

1. 1.Is this pharmacy certified in the REMS program for my capsules?
2. 2.When do I need pregnancy tests, and what should I do if my birth control pill causes spotting?
3. 3.How do I step down if I need to stop?
4. 4.Is it safe with my water pill, seizure medicine, or sleep or anxiety medicines?

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