Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
Make sure your doctor knows if you are using naloxone, naltrexone, medicine to treat HIV or AIDS (such as nevirapine, efavirenz, ritonavir, lopinavir, zidovudine, didanosine, or stavudine), medicine to treat fungal infection (such as ketoconazole, clotrimazole, Nizoral®), rifampin, phenytoin, phenobarbital, carbamazepine, or St. John's Wort. Also tell your doctor if you are using a monoamine (MAO) inhibitor (such as Eldepryl®, Marplan®, Nardil®, or Parnate®) or have used one within the past 14 days.
Tell your doctor if you are taking medicine to treat bacterial infection (such as erythromycin, clarithromycin, Biaxin®, Ery-tab®), medicine for heart rhythm problems (such as quinidine, disopyramide, amiodarone, Norpace®, Cordarone®), medicine to treat mental illness (such as haloperidol, prochlorperazine, Haldol®, Mellaril®), blood pressure medicine (such as diltiazem, nifedipine, verapamil, Lotrel®, Norvasc®), or medicine to treat depression (such as sertraline, fluvoxamine, amitriptyline, desipramine, Zoloft®, Prozac®). Also tell your doctor if you are using diuretics ("water pills" such as hydrochlorothiazide (HCTZ), furosemide, Demadex®, Lasix®), laxatives (stool softeners), or hormone medicines.
Tell your doctor if you are using any medicines that make you sleepy. These include sleeping pills, cold and allergy medicine, narcotic pain relievers (such as pentazocine, nalbuphine, butorphanol, buprenorphine), sedatives, and certain illegal ("street") drugs.
Do not drink alcohol while you are using this medicine.
Make sure your doctor knows if you are pregnant or breastfeeding, or if you have heart disease, breathing problems, head injury, liver disease, kidney disease, stomach problems (such as severe stomach pain), low blood pressure, thyroid problems, Addison's disease, prostate problems, or trouble urinating. Tell your doctor if you also have a history of heart rhythm problems such as QT prolongation.
This medicine may be habit-forming. If you feel that the medicine is not working as well, do not use more than your prescribed dose. Call your doctor for instructions.
Do not stop using this medicine suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.
This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert. Change your positions slowly when getting up from a lying or sitting position.
This medicine may cause constipation. This is more common if you use it for a long time. Ask your doctor if you should also use a laxative to prevent and treat constipation.