Brand Names: Qsymia
Generic Name: phentermine and topiramate
- What is phentermine and topiramate (Qsymia)?
- What are the possible side effects of phentermine and topiramate (Qsymia)?
- What is the most important information I should know about phentermine and topiramate (Qsymia)?
- What should I discuss with my healthcare provider before taking phentermine and topiramate (Qsymia)?
- How should I take phentermine and topiramate (Qsymia)?
- What happens if I miss a dose (Qsymia)?
- What happens if I overdose (Qsymia)?
- What should I avoid while taking phentermine and topiramate (Qsymia)?
- What other drugs will affect phentermine and topiramate (Qsymia)?
- Where can I get more information (Qsymia)?
What is phentermine and topiramate (Qsymia)?
This medicine is sometimes used to treat obesity that may be related to diabetes, high cholesterol, or high blood pressure. Phentermine and topiramate will not treat these underlying conditions. Keep using any other medicines your doctor has prescribed.
Phentermine and topiramate may also be used for purposes not listed in this medication guide.
What are the possible side effects of phentermine and topiramate (Qsymia)?
Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), depressed, or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have:
- unusual changes in mood or behavior;
- confusion, trouble concentrating, problems with speech or memory;
- fast or pounding heartbeats while you are resting;
- a seizure;
- signs of a kidney stone--severe pain in your side or lower back, painful or difficult urination; or
- signs of too much acid in your blood--loss of appetite, tiredness, thinking problems, irregular heartbeats.
Common side effects may include:
- numbness or tingly feeling;
- sleep problems (insomnia); or
- dry mouth, changes in your sense of taste.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What is the most important information I should know about phentermine and topiramate (Qsymia)?
Topiramate may cause vision problems that can be permanent if not treated quickly. Call your doctor right away if you have a sudden decrease in vision.
Some people have thoughts about suicide while taking topiramate. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.
Tell your doctor if you have fast or pounding heartbeats while you are resting.
What should I discuss with my healthcare provider before taking phentermine and topiramate (Qsymia)?
Do not use this medicine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.
You should not use this medicine if you are allergic to phentermine or topiramate, or if you have:
You may need to have a negative pregnancy test before starting this treatment. Do not use phentermine and topiramate if you are pregnant. Stop taking this medicine and call your doctor right away if you become pregnant.
Topiramate may increase the risk of cleft lip and palate in a newborn. This birth defect occurs early in pregnancy, and can develop even before you know you are pregnant. Weight loss during pregnancy also can harm an unborn baby, even if you are overweight. Use effective birth control to prevent pregnancy while you are using phentermine and topiramate.
Phentermine and topiramate is not approved for use by anyone younger than 18 years old.
Tell your doctor if you have ever had:
- heart problems, high blood pressure;
- a heart attack or stroke;
- diabetes (weight loss may cause low blood sugar);
- metabolic acidosis (too much acid in your blood);
- soft or brittle bones (osteomalacia, osteopenia, osteoporosis);
- kidney disease, kidney stones, or dialysis;
- liver disease;
- mood problems, depression, or suicidal thoughts or actions;
- a seizure; or
- chronic diarrhea.
Topiramate can increase the level of acid in your blood (metabolic acidosis). This can weaken your bones, cause kidney stones, or cause growth problems in children or harm to an unborn baby. You may need blood tests to make sure you do not have metabolic acidosis.
Some people have thoughts about suicide while taking topiramate. Your doctor will need to check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
You should not breast-feed while using this medicine.
How should I take phentermine and topiramate (Qsymia)?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.
Take this medicine each morning, with or without food.
Drink plenty of water each day to prevent dehydration or kidney stones while you are taking phentermine and topiramate.
Your doctor may change your dose or tell you to stop taking this medicine if you have not lost a certain amount of weight during the first 12 weeks. Follow your doctor's dosing instructions very carefully. You must also follow a low-calorie diet.
Do not stop using phentermine and topiramate suddenly or you could have a seizure (convulsions). Follow your doctor's instructions about tapering your dose.
Store at room temperature away from moisture and heat.
Phentermine may be habit-forming. Misuse can cause addiction, overdose, or death. Keep the medication in a place where others cannot get to it. Selling or giving away this medicine is against the law.
What happens if I miss a dose (Qsymia)?
Skip the missed dose and use your next dose at the regular time. Do not use two doses at one time.
What happens if I overdose (Qsymia)?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of phentermine and topiramate can be fatal.
Overdose symptoms may include confusion, hallucinations, panic, personality changes, tremors, a restless feeling followed by severe tiredness, nausea, vomiting, diarrhea, stomach cramps, irregular heartbeat, rapid breathing, seizure, or coma.
What should I avoid while taking phentermine and topiramate (Qsymia)?
Do not take other weight-loss products without your doctor's advice.
Ketogenic or "ketosis" diets that are high in fat and low in carbohydrates can increase the risk of metabolic acidosis. Avoid the use of such diets while you are taking this medicine.
Drinking alcohol with this medicine can cause side effects.
Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.
Avoid becoming overheated or dehydrated in hot weather. Topiramate can decrease sweating and increase body temperature, leading to life-threatening dehydration.
What other drugs will affect phentermine and topiramate (Qsymia)?
Phentermine and topiramate can cause irregular vaginal bleeding while you are taking birth control pills. This should not make the pills less effective in preventing pregnancy.
Using this medicine with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.
Tell your doctor about all your other medicines, especially:
- valproic acid or divalproex sodium (Depakene or Depakote)
- birth control pills;
- a diuretic or "water pill"; or
- insulin or oral diabetes medicine.
This list is not complete. Other drugs may affect phentermine and topiramate, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
Where can I get more information (Qsymia)?
Your doctor or pharmacist can provide more information about phentermine and topiramate.
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