Phentermine-Topiramate Capsule, Extended Release Multiphase 24 Hr (Capsule, ER Hr)

Side Effects

Dizziness, drowsiness, dry mouth, difficulty sleeping, tiredness, tingling of the hands/feet, constipation, and metallic taste may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: temporary difficulty concentrating/finding words/remembering things, signs of kidney stones (such as painful urination, fever, chills, pink/bloody urine), rapid breathing, fast/slow/irregular heartbeat, bone pain/broken bones, loss of consciousness, change in sexual ability/interest, unusual bleeding/bruising.

A small number of people who take anticonvulsants for any reason (such as seizure, bipolar disorder, pain) may experience depression, suicidal thoughts/attempts, or other mental/mood problems. Tell your doctor right away if you or your family/caregiver notice any unusual/sudden changes in your mood, thoughts, or behavior including signs of depression, suicidal thoughts/attempts, thoughts about harming yourself.

Rarely, topiramate may cause a very serious eye problem, generally within 1 month of starting treatment. If untreated, this eye problem can lead to permanent blindness. Therefore, get medical help right away if any of these side effects occur: sudden vision changes (such as decreased vision, blurred vision), eye pain/redness.

This medication can rarely cause a serious metabolic problem (high amount of ammonia in the blood), especially if you are also taking valproic acid. Tell your doctor right away if you experience sudden/unexplained tiredness, vomiting, or mental changes (such as decreased alertness).

Get medical help right away if you have any very serious side effects, including: severe headache, slurred speech, seizure, weakness on one side of the body.

This drug may rarely cause serious (sometimes fatal) lung or heart problems (pulmonary hypertension, heart valve problems). The risk may increase with longer use of this medication and use of other appetite-suppressant drugs/herbal products along with this drug. Stop taking this medication and get medical help right away if you have any very serious side effects, including: chest pain, difficulty breathing with exercise/decreased ability to exercise, fainting, swelling of the legs/ankles/feet.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking this medication, tell your doctor or pharmacist if you are allergic to it; or to any other sympathomimetic amines (including decongestants such as pseudoephedrine, stimulants such as amphetamine, appetite suppressants such as diethylpropion); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: high blood pressure, glaucoma, personal or family history of a substance use disorder (such as overuse of or addiction to drugs/alcohol), heart disease (such as chest pain, heart attack, heart murmur, fast/irregular heartbeat, heart valve problems), mental/mood problems (such as depression, thoughts of suicide, severe anxiety/agitation), high blood pressure in the lungs (pulmonary hypertension), stroke, overactive thyroid (hyperthyroidism), seizures, kidney disease (including kidney stones), liver disease, a certain metabolic imbalance (metabolic acidosis), a diet high in fat and low in carbohydrates (ketogenic diet).

This drug may make you dizzy or drowsy or blur your vision. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

This medication may make you sweat less, making you more likely to get heat stroke. Avoid doing things that may cause you to overheat, such as hard work or exercise in hot weather, or using hot tubs. When the weather is hot, drink a lot of fluids and dress lightly. If you overheat, quickly look for a place to cool down and rest. Get medical help right away if you have a fever that does not go away, mental/mood changes, headache, or dizziness.

If you have diabetes, check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication during treatment with this medication.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially dizziness and high blood pressure. Dizziness can increase the risk of falling.

Children may be more sensitive to the side effects of this drug, especially weakened bones, slowed growth rate, and decreased sweating. Consult your doctor or pharmacist for more details.

This medication must not be used during pregnancy. It may harm an unborn baby. Discuss the use of reliable forms of birth control with your doctor. If you become pregnant or think you may be pregnant, tell your doctor right away. You will need to have a negative pregnancy test before starting this medication. You will also need to take a pregnancy test every month while on this medication.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication.

Topiramate passes into breast milk. It is unknown if phentermine passes into breast milk; however, similar drugs pass into breast milk. This medication may have undesirable effects on a nursing infant. Therefore, breast-feeding while using this medication is not recommended. Consult your doctor before breast-feeding.

Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Taking MAO inhibitors with this medication may cause a serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine) during treatment with this medication. Most MAO inhibitors should also not be taken for two weeks before treatment with this medication. Ask your doctor when to start or stop taking this medication.

This drug should not be used with certain medications because very serious interactions may occur. If you are taking or have taken other appetite-suppressant drugs in the past year (such as diethylpropion, ephedra/ma huang), tell your doctor or pharmacist before starting this medication.

Some products that may interact with this drug include: orlistat, other stimulants (including amphetamines, methylphenidate, street drugs such as cocaine or MDMA/"ecstasy").

Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, marijuana (cannabis), antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and opioid pain relievers (such as codeine).

Some products have ingredients that could raise your heart rate or blood pressure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products or diet aids).

If you are taking hormonal birth control (such as pills, patch, or ring) with this medication, tell your doctor if you have any new spotting or breakthrough bleeding.

Caffeine can increase the side effects of this medication. Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas), eating large amounts of chocolate, or taking nonprescription products that contain caffeine.

This medication may interfere with certain medical/laboratory tests (including brain scan for Parkinson's disease), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: rapid breathing, unusual restlessness, fast/slow/irregular heartbeat, chest pain, hallucinations, seizures, loss of consciousness, severe drowsiness.

Notes

Do not share this medication with others. Sharing it is against the law.

Lab and/or medical tests (such as blood pressure, heart rate, heart tests, eye exams, kidney function, blood sugar, potassium and bicarbonate blood levels) should be done before you start taking this medication and while you are taking it. Keep all medical and lab appointments. Consult your doctor for more details.

Missed Dose

If you miss a dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.Information last revised April 2020. Copyright(c) 2020 First Databank, Inc.