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Cosopt Side Effects
Serious Side Effects
Some side effects with Cosopt, while occurring infrequently, are potentially serious and should be reported immediately to your healthcare provider. Dorzolamide, one of the active ingredients, is a sulfonamide drug and therefore has the potential to cause severe allergic reactions. Be sure to let your healthcare provider know immediately if you develop any signs or symptoms of an allergic reaction, such as:- An unexplained rash or hives
- Itching
- Unexplained swelling, especially of the mouth, lips, or throat
- Wheezing or difficulty breathing.
Timolol, the other active ingredient in Cosopt, is a beta blocker that can cause serious, although rare, side effects, such as:
- A slow heart rate (bradycardia)
- Low blood pressure (hypotension)
- Worsening of asthma or chronic obstructive pulmonary disease (COPD)
- Depression
- Hallucinations
- Heart attacks or strokes
- Anxiety
- Signs of myasthenia gravis, such as muscle weakness, droopy eyelids, and double vision
- Signs of heart failure, such as:
- Water retention
- Swelling in the hands or feet
- Rapid weight gain (see Timolol and Weight Gain)
- Coughing
- Difficulty breathing
- Shortness of breath.
Of course, any eye drop can cause problems (such as an eye infection) if it is contaminated, so be sure to avoid touching the tip of the dropper to any surface, including the surface of the eye. Report any signs of an eye infection (such as severe pain, swelling, or redness) to your healthcare provider right away.
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD