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 (e.g., diethylpropion, ephedra/ma huang), tell your doctor or pharmacist before starting this medication.
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, 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.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially: drugs for depression (e.g., TCAs such as imipramine, SSRIs and SNRIs such as paroxetine, fluoxetine, venlafaxine, duloxetine), high blood pressure medicine (e.g., guanethidine, methyldopa), phenothiazines (e.g., prochlorperazine, promethazine, chlorpromazine), other stimulants (e.g., amphetamines, methylphenidate, street drugs such as cocaine or MDMA/"ecstasy").
Tell your doctor or pharmacist if you also take drugs that cause dizziness or drowsiness such as: certain antihistamines (e.g., diphenhydramine), anti-seizure drugs (e.g., carbamazepine), medicine for sleep or anxiety (e.g., alprazolam, diazepam, zolpidem), muscle relaxants, narcotic pain relievers (e.g., codeine), psychiatric medicines (e.g., risperidone, amitriptyline, trazodone).
Also report the use of drugs which might increase seizure risk when combined with this medication such as isoniazid (INH), phenothiazines (e.g., thioridazine), theophylline, or tricyclic antidepressants (e.g., amitriptyline), among others.
Check the labels on all your medicines/herbal products (e.g., cough-and-cold products containing decongestants such as pseudoephedrine, diet aids such as phenylpropanolamine, ephedra/ma huang) because they may contain ingredients that could increase your heart rate or blood pressure. Ask your pharmacist about using those products safely.
Caffeine can increase the side effects of this medication. Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas) or eating large amounts of chocolate.
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.