Side Effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
More common- Abnormal thinking: holding false beliefs that cannot be changed by fact
- Agitation
- Anxiety
- Clenching or grinding of teeth
- Clumsiness or unsteadiness
- Confusion
- Difficulty swallowing
- Dizziness
- Excessive watering of mouth
- False sense of well being
- Feeling faint
- General feeling of discomfort or illness
- Hallucinations (seeing, hearing, or feeling things that are not there)
- Hand tremor, increased
- Nausea or vomiting
- Numbness
- Unusual and uncontrolled movements of the body, including the face, tongue, arms, hands, head, and upper body
- Unusual tiredness or weakness
- Blurred vision
- Difficult urination
- Difficulty opening mouth
- Dilated (large) pupils
- Dizziness or lightheadedness when getting up from a lying or sitting position
- Double vision
- Fast, irregular, or pounding heartbeat
- Hot flashes
- Increased blinking or spasm of eyelids
- Loss of bladder control
- Mental depression
- Other mood or mental changes
- Skin rash
- Unusual weight gain or loss
- Back or leg pain
- Bloody or black tarry stools
- Chills
- Convulsions (seizures)
- Fever
- High blood pressure
- Inability to move eyes
- Loss of appetite
- Pain, tenderness, or swelling of foot or leg
- Pale skin
- Prolonged, painful, inappropriate penile erection
- Sore throat
- Stomach pain
- Swelling of face
- Swelling of feet or lower legs
- Vomiting of blood or material that looks like coffee grounds
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common- Abdominal pain
- Dryness of mouth
- Loss of appetite
- Nightmares
- Passing gas
- Constipation
- Diarrhea
- Flushing of skin
- Headache
- Hiccups
- Increased sweating
- Muscle twitching
- Trouble in sleeping
This medicine may sometimes cause the urine, saliva, and sweat to be darker in color than usual. The urine may at first be reddish, then turn to nearly black after being exposed to air. Some bathroom cleaning products will produce a similar effect when in contact with urine containing this medicine. This is to be expected during treatment with this medicine. Also, this medicine may cause a bitter taste, or a burning sensation of the tongue.
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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