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Phentermine hydrochloride is indicated as a short-term (a few weeks) adjunct in a regimen of weight reduction based on exercise, behavioral modification and caloric restriction in the management of exogenous obesity for patients with an…
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Phentermine hydrochloride is indicated as a short-term (a few weeks) adjunct in a regimen of weight reduction based on exercise, behavioral modification and caloric restriction in the management of exogenous obesity for patients with an initial body mass index ≥ 30 kg/m 2, or ≥ 27 kg/m 2 in the presence of other risk factors (e.g., controlled hypertension, diabetes, hyperlipidemia).
Below is a chart of body mass index (BMI) based on various heights and weights. BMI is calculated by taking the patient's weight, in kilograms (kg), divided by the patient's height, in meters (m), squared. Metric conversions are as follows: pounds ÷ 2.2 = kg; inches × 0.0254 = meters. BODY MASS INDEX (BMI), kg/m 2 The limited usefulness of agents of this class, including phentermine hydrochloride tablets, should be measured against possible risk factors inherent in their use such as those described below.
Phentermine hydrochloride is a sympathomimetic amine anorectic indicated as a short-term adjunct (a few weeks) in a regimen of weight reduction based on exercise, behavioral modification and caloric restriction in the management of exogenous obesity for patients with an initial body mass index ≥ 30 kg/m 2, or ≥ 27 kg/m 2 in the presence of other risk factors (e.g., controlled hypertension, diabetes, hyperlipidemia).
The limited usefulness of agents of this class, including phentermine hydrochloride, should be measured against possible risk factors inherent in their use. Figure
Phentermine and topiramate extended-release capsules can cause serious side effects, including: Birth defects. If you take phentermine and topiramate extended-release capsules during pregnancy, your baby has a higher risk for birth defects including cleft lip and cleft palate. Your baby may also be smaller than expected at birth.
The long-term effects of this are not known. These defects can begin early in pregnancy, even before you know you are pregnant. Patients who are pregnant must not take phentermine and topiramate extended-release capsules. Patients who can become pregnant should: Have a pregnancy test before taking phentermine and topiramate extended-release capsules and every month while taking phentermine and topiramate extended-release capsules.
Use effective birth control (contraception) consistently while taking phentermine and topiramate extended-release capsules. Talk to your health care provider about how to prevent pregnancy. If you become pregnant while taking phentermine and topiramate extended-release capsules, stop taking phentermine and topiramate extended-release capsules immediately and tell your health care provider right away.
Health care providers and patients who become pregnant should report all cases of pregnancy to: FDA MedWatch at 1-800-FDA-1088 Because of the risk for birth defects (cleft lip and cleft palate), phentermine and topiramate extended-release capsules are available through a restricted program called the phentermine and topiramate extended-release capsules Risk Evaluation and Mitigation Strategy (REMS).
Phentermine and topiramate extended-release capsules are only available through certified pharmacies that participate in the phentermine and topiramate extended-release capsules REMS program. Your health care provider can give you information about how to find a certified pharmacy. For more information, go to www.PhenTopREMS or call 1‐800‐269‐6816.
Suicidal thoughts or actions. Topiramate, an ingredient in phentermine and topiramate extended-release capsules, may cause you to have suicidal thoughts or actions. Call your health care provider right away if you have any of these symptoms, especially if they are new, worse, or worry you: thoughts about suicide or dying attempts to commit suicide new or worse depression new or worse anxiety feeling agitated or restless panic attacks trouble sleeping (insomnia) new or worse irritability acting aggressive, being angry, or violent acting on dangerous impulses an extreme increase in activity and talking (mania) other unusual changes in behavior or mood Do not stop phentermine and topiramate extended-release capsules without first talking to a health care provider.
Stopping phentermine and topiramate extended-release capsules suddenly can cause serious problems. Suicidal thoughts or actions can be caused by things other than medicines. If you have suicidal thoughts or actions, your health care provider may check for other causes. How can I watch for early symptoms of suicidal thoughts and actions?
Pay attention to any changes, especially sudden changes in mood, behaviors, thoughts, or feelings. Keep all follow-up visits with your health care provider as scheduled. Call your health care provider between visits as needed, especially if you are worried about symptoms. Serious eye problems which include: any sudden decrease in vision, with or without eye pain and redness, a blockage of fluid in the eye causing increased pressure in the eye (secondary angle closure glaucoma).
These problems can lead to permanent vision loss if not treated. Tell your health care provider right away if you have any new eye symptoms. Phentermine and topiramate extended-release capsules can have other serious side effects. See "
Your health care provider should start you on a diet and exercise program when you start taking phentermine and topiramate extended-release capsules. Stay on this program while you are taking phentermine and topiramate extended-release capsules. Take phentermine and topiramate extended-release capsules exactly as your health care provider tells you to take them.
Do not change your dose without talking to your health care provider. Take phentermine and topiramate extended-release capsules daily in the morning. Phentermine and topiramate extended-release capsules can be taken with or without food. If you miss a dose of phentermine and topiramate extended-release capsules, wait until the next morning to take your usual dose of phentermine and topiramate extended-release capsules.
Do not double your dose. To start treatment with phentermine and topiramate extended-release capsules Take 1 phentermine and topiramate extended-release capsule 3.75 mg/23 mg (Figure A) 1 time each morning for the first 14 days. After taking phentermine and topiramate extended-release capsules 3.75 mg/23 mg for 14 days, then take 1 phentermine and topiramate extended-release capsule 7.5 mg/46 mg (Figure B) 1 time each morning.
After taking phentermine and topiramate extended-release capsules for 12 weeks Your health care provider may tell you to increase your dose of phentermine and topiramate extended-release capsules if you do not lose a certain amount of weight within the first 12 weeks of treatment at the recommended dose. If your health care provider increases the dose of phentermine and topiramate extended-release capsules Take 1 phentermine and topiramate extended-release capsule 11.25 mg/69 mg (Figure C) 1 time each morning for 14 days.
After taking 14 days of phentermine and topiramate extended-release capsules 11.25 mg/69 mg, then take 1 phentermine and topiramate extended-release capsule 15 mg/92 mg (Figure D) 1 time each morning. Stopping phentermine and topiramate extended-release capsules treatment Your health care provider should tell you to stop taking phentermine and topiramate extended-release capsules if you have not lost a certain amount of weight after an additional 12 weeks of treatment on the higher dose.
Do not stop taking phentermine and topiramate extended-release capsules without talking to your health care provider. Stopping phentermine and topiramate extended-release capsules suddenly can cause serious problems, such as seizures. Your health care provider will tell you how to stop taking phentermine and topiramate extended-release capsules slowly.
If you take too much phentermine and topiramate extended-release capsules, call your health care provider or Poison Help line at 1-800-222-1222 or go to the nearest emergency room right away.
" What are phentermine and topiramate extended-release capsules? Phentermine and topiramate extended-release capsules are a prescription medicine that contains phentermine and topiramate extended-release. Phentermine and topiramate extended-release capsules may help adults with obesity or some adults with overweight who also have weight-related medical problems, to help them lose excess body weight and keep the weight off.
Phentermine and topiramate extended-release capsules should be used with a reduced calorie diet and increased physical activity. It is not known if phentermine and topiramate extended-release capsules changes your risk of heart problems or stroke or of death due to heart problems or stroke. It is not known if phentermine and topiramate extended-release capsules are safe and effective when taken with other prescription and over-the-counter medicines, or herbal weight loss products.
It is not known if phentermine and topiramate extended-release capsules are safe and effective in children under 12 years old. Phentermine and topiramate extended-release capsules are a federally controlled substance (CIV) because it contains phentermine and can be abused or lead to drug dependence. Keep phentermine and topiramate extended-release capsules in a safe place, to protect them from theft.
Never give your phentermine and topiramate extended-release capsules to anyone else, because they may cause death or harm them. Selling or giving away phentermine and topiramate extended-release capsules is against the law.
Do not take phentermine and topiramate extended-release capsules if you: are pregnant, planning to become pregnant, or become pregnant during phentermine and topiramate extended-release capsules treatment. have glaucoma. have thyroid problems (hyperthyroidism). are taking certain medicines called monoamine oxidase inhibitors (MAOIs) or have taken MAOIs in the past 14 days.
are allergic to topiramate, sympathomimetic amines such as phentermine, or any of the ingredients in phentermine and topiramate extended-release capsules. See the end of this Medication Guide for a complete list of ingredients in phentermine and topiramate extended-release capsules. Before taking phentermine and topiramate extended-release capsules, tell your health care provider about all of your medical conditions, including if you: have or have had depression, mood problems, or suicidal thoughts or behavior.
have eye problems, especially glaucoma. See " Who should not take phentermine and topiramate extended-release capsules? " have a history of too much acid in the blood (metabolic acidosis) or a condition that puts you at higher risk for metabolic acidosis such as chronic diarrhea, surgery, a diet high in fat and low in carbohydrates (ketogenic diet), weak, brittle, or soft bones (osteoporosis, osteomalacia (rickets), osteopenia), or decreased bone density.
have kidney problems, kidney stones, or are getting kidney dialysis. have liver problems. have seizures or convulsions (epilepsy). are allergic to FD&C Yellow No. 5 (tartrazine) are breastfeeding or plan to breastfeed. Phentermine and topiramate can pass into your breast milk and may harm your baby. You and your health care provider should decide if you will take phentermine and topiramate extended-release capsules or breastfeed.
You should not do both. Tell your health care provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Phentermine and topiramate extended-release capsules taken with other medicines may affect how each medicine works and may cause side effects. Especially tell your health care provider if you take: Birth control pills.
Tell your health care provider if your menstrual bleeding changes while you are taking birth control pills that contain both estrogen and progestin (combination oral contraceptives) and phentermine and topiramate extended-release capsules. Water pills (diuretics) such as hydrochlorothiazide (HCTZ). Any medicines that impair or decrease your thinking, concentration, or muscle coordination.
Carbonic anhydrase inhibitors such as ZONEGRAN (zonisamide), DIAMOX (acetazolamide) or NEPTAZANE (methazolamide). Seizure medicines such as Valproic acid (DEPAKENE or DEPAKOTE). Ask your health care provider or pharmacist for a list of these medicines, if you are not sure. Know the medicines you take. Keep a list of them to show your health care provider and pharmacist each time you get a new medicine.
Do not start a new medicine without talking to your health care provider.
Do not get pregnant while taking phentermine and topiramate extended-release capsules. Do not drink too much alcohol while taking phentermine and topiramate extended-release capsules. Phentermine and topiramate extended-release capsules and alcohol can affect each other causing side effects such as sleepiness or dizziness.
Do not drive a car, operate heavy machinery, or do other dangerous activities until you know how phentermine and topiramate extended-release capsules affects you. Phentermine and topiramate extended-release capsules can slow your thinking and motor skills and may affect vision. What are the possible side effects of phentermine and topiramate extended-release capsules?
Phentermine and topiramate extended-release capsules can cause serious side effects, including: Mood changes and trouble sleeping. Phentermine and topiramate extended-release capsules may cause depression or mood problems, and trouble sleeping. Tell your health care provider if symptoms occur. Concentration, memory, and speech difficulties.
Phentermine and topiramate extended-release capsules may affect how you think and cause confusion, problems with concentration, attention, memory, or speech. Tell your health care provider if symptoms occur. Slowing of growth. Phentermine and topiramate extended-release capsules may slow the increase in height in children when used for a long time.
Increases of acid in bloodstream (metabolic acidosis). If left untreated, metabolic acidosis can cause brittle or soft bones (osteoporosis, osteomalacia (rickets), osteopenia), kidney stones, can slow the rate of growth in children, and may possibly harm your baby if you are pregnant. Metabolic acidosis can happen with or without symptoms.
Sometimes people with metabolic acidosis will: feel tired not feel hungry (loss of appetite) feel changes in heartbeat have trouble thinking clearly Your health care provider should do a blood test to measure the level of acid in your blood before and during your treatment with phentermine and topiramate extended-release capsules.
Decrease in kidney function. Phentermine and topiramate extended-release capsules may cause a decrease in kidney function. Your health care provider should do a blood test to measure your kidney function before and during treatment with phentermine and topiramate extended-release capsules. Possible seizures if you stop taking phentermine and topiramate extended-release capsules too fast.
Seizures may happen in people who may or may not have had seizures in the past if you stop phentermine and topiramate extended-release capsules too fast. Your health care provider will tell you how to stop taking phentermine and topiramate extended-release capsules slowly. Kidney stones. Drink plenty of fluids when taking phentermine and topiramate extended-release capsules to help decrease your chances of getting kidney stones.
If you get severe side or back pain, or blood in your urine, call your health care provider. Decreased sweating and increased body temperature (fever). People should be watched for signs of decreased sweating and fever, especially in hot temperatures. Some people may need to be hospitalized for this condition. Low potassium.
Phentermine and topiramate extended-release capsules can increase your risk of low potassium levels. Your health care provider should do a blood test to measure the level of potassium in your blood before and during treatment with phentermine and topiramate extended-release capsules. Severe multiorgan reactions. Treatment with phentermine and topiramate capsules may cause a serious allergic reaction that may affect your skin or other parts of your body such as your liver, kidneys, heart, or blood cells.
This allergic reaction can be life
Store phentermine and topiramate extended-release capsules at room temperature between 20°C to 25°C (68°F to 77°F). Keep phentermine and topiramate extended-release capsules in a tightly closed container. Keep phentermine and topiramate extended-release capsules dry and away from moisture. Keep phentermine and topiramate extended-release capsules and all medicines out of the reach of children.
sofidex [Internet]. Daloreum; c2026. Phentermine; [reviewed 2026 Aug 2; cited 2026 Nov 10]. Available from: https://sofidex.com/patients/medicines/phentermine
sofidex. (2026, August 2). Phentermine. Daloreum. Retrieved November 10, 2026, from https://sofidex.com/patients/medicines/phentermine
Phentermine. sofidex. Reviewed August 2, 2026. Accessed November 10, 2026. https://sofidex.com/patients/medicines/phentermine
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