What is the most important information I should know about Tegopen (cloxacillin)?

Take all of the cloxacillin that has been prescribed for you even if you begin to feel better. Your symptoms may begin to improve before the infection is completely treated. Do not break, chew, open, or crush the capsules. Swallow them whole. Cloxacillin may decrease the effectiveness of birth control pills. Use a second method of birth control while taking cloxacillin to protect against pregnancy.

Tegopen (cloxacillin) side effects

If you experience any of the following serious side effects, stop taking cloxacillin and seek emergency medical attention:

• an allergic reaction (shortness of breath; closing of your throat; hives; swelling of your lips, face, or tongue; rash; or fainting);
• seizures;
• severe watery diarrhea and abdominal cramps; or
• unusual bleeding or bruising.

Other, less serious side effects maybe more likely to occur. Continue to take cloxacillin and talk to your doctor if you experience

• mild nausea, vomiting, diarrhea, or abdominal pain;
• white patches on the tongue (thrush/yeast infection);
• itching or discharge of the vagina (vaginal yeast infection); or
• black, "hairy" tongue or sore mouth or tongue.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.