What should I watch for?
Tell your doctor or health care professional if your pain does not go away, if it gets worse, or if you have a new or a different type of pain. You may develop tolerance to the medicine. Tolerance means that you will need a higher dose of the medicine for pain relief. Tolerance is normal and is expected if you take the medicine for a long time.
Do not suddenly stop taking your medicine because you may develop a severe reaction. Your body becomes used to the medicine. This does NOT mean you are addicted. Addiction is a behavior related to getting and using a drug for a non-medical reason. If you have pain, you have a medical reason to take pain medicine. Your doctor will tell you how much medicine to take. If your doctor wants you to stop the medicine, the dose will be slowly lowered over time to avoid any side effects.
If you are also taking a narcotic medicine for pain or cough or another medicine that also causes drowsiness, you may have more side effects. Give your health care provider a list of all medicines you use. Your doctor will tell you how much medicine to take. Do not take more medicine than directed. Call emergency for help if you have problems breathing or unusual sleepiness.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.
The medicine will cause constipation. Try to have a bowel movement at least every 2 to 3 days. If you do not have a bowel movement for 3 days, call your doctor or health care professional.
Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.
Side Effects to watch for
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
- breathing problems
- signs and symptoms of a dangerous change in heartbeat or heart rhythm like chest pain; dizziness; fast or irregular heartbeat; palpitations; feeling faint or lightheaded, falls; breathing problems
- signs and symptoms of liver injury like dark yellow or brown urine; general ill feeling or flu-like symptoms; light-colored stools; loss of appetite; nausea; right upper belly pain; unusually weak or tired; yellow of the eyes or skin
- signs and symptoms of low blood pressure like dizziness; feeling faint or lightheaded, falls; unusually weak or tired
- trouble passing urine or change in the amount of urine
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
What may interact with this drug?
Do not take this medication with any of the following medicines:
- certain medicines for fungal infections like ketoconazole and itraconazole
This medicine may interact with the following medications:
- antihistamines for allergy, cough and cold
- antiviral medicines for HIV or AIDS
- certain antibiotics like clarithromycin, erythromycin, linezolid, rifampin
- certain medicines for anxiety or sleep
- certain medicines for bladder problems like oxybutynin, tolterodine
- certain medicines for depression like amitriptyline, fluoxetine, sertraline
- certain medicines for migraine headache like almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, sumatriptan, zolmitriptan
- certain medicines for nausea or vomiting like dolasetron, ondansetron, palonosetron
- certain medicines for Parkinson's disease like benztropine, trihexyphenidyl
- certain medicines for seizures like phenobarbital, primidone
- certain medicines for stomach problems like cimetidine, dicyclomine, hyoscyamine
- certain medicines for travel sickness like scopolamine
- general anesthetics like halothane, isoflurane, methoxyflurane, propofol
- local anesthetics like lidocaine, pramoxine, tetracaine
- MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate
- medicines that relax muscles for surgery
- methylene blue
- other medicines that prolong the QT interval (cause an abnormal heart rhythm)
- other narcotic medicines for pain or cough
- phenothiazines like chlorpromazine, mesoridazine, prochlorperazine, thioridazine