• Basic Info
• Top Questions
• Interactions

Some drugs may decrease the effects of cloxacillin and prevent it from properly treating your infection. Before taking cloxacillin, tell your doctor if you are taking any of the following drugs:

• cholestyramine (Questran) or colestipol (Colestid); or

• another antibiotic (for the same or for a different infection) such as erythromycin (Ery-Tab, E-Mycin, E.E.S., others), tetracycline (Sumycin, others), minocycline (Minocin), doxycycline (Doryx, Vibramycin, others), or any other.

Cloxacillin may decrease the effectiveness of birth control pills. Use a second method of birth control while taking cloxacillin to protect against pregnancy.

Cloxacillin increases the effects of methotrexate, and you may need a dose adjustment during therapy with cloxacillin.

Cloxacillin also increases the side effects of allopurinol (Zyloprim) and may cause a rash.

Probenecid (Benemid) increases the effects of cloxacillin. These drugs may be used together for this purpose; however, be sure your doctor is aware if you are taking probenecid. You may need a lower dose of cloxacillin.

Drugs other than those listed here may also interact with cloxacillin. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines.

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.