Side Effects of This Medicine

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 immediately if any of the following side effects occur:

Signs and symptoms of overdose

Difficulty in breathing; dizziness (extreme) or faintness; feeling cold; pinpoint pupils of eyes; slow heartbeat; unusual tiredness or weakness (extreme)

Check with your doctor as soon as possible if any of the following side effects occur:

More common—with transdermal system (skin patch) only

Itching or redness of skin

Less common

Mental depression; swelling of feet and lower legs

Rare

Paleness or cold feeling in fingertips and toes; vivid dreams or nightmares

Other 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. However, check with your doctor if any of the following side effects continue or are bothersome:

More common

Constipation; dizziness; drowsiness; dryness of mouth; unusual tiredness or weakness

Less common

Darkening of skin—with transdermal system (skin patch) only; decreased sexual ability; dizziness, lightheadedness, or fainting, especially when getting up from a lying or sitting position; dry, itching, or burning eyes; loss of appetite; nausea or vomiting; nervousness

After you have been using this medicine for a while, it may cause unpleasant or even harmful effects if you stop taking it too suddenly. After you stop taking this medicine, check with your doctor immediately if any of the following occur:

Anxiety or tenseness; chest pain; fast or pounding heartbeat; headache; increased salivation; nausea; nervousness; restlessness; shaking or trembling of hands and fingers; stomach cramps; sweating; trouble in sleeping; vomiting

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.