Certain side effects of this medicine are not unusual and may even disappear during treatment. If any of the following effects persist or are severe, consult your doctor.
- diarrhoea
- nausea, vomiting
- stomach upset or discomfort
Although uncommon, you may develop a black, "hairy" tongue while taking penicillin. This effect is harmless and usually goes away after treatment. Maintain good oral hygiene, and brush your tongue with a soft toothbrush twice a day.
Consult your doctor as soon as possible if any of these additional effects occur, as they may indicate more serious side effects:
- allergic reaction (difficulty breathing, severe dizziness, rash, itching, swelling)
- sores in the mouth, red painful eyes or blisters on the skin
- vaginal itching or discharge
- white spots on lips or in mouth
This medication may rarely cause a severe intestinal condition (pseudomembranous colitis) due to a resistant bacteria. This condition may occur during treatment or weeks after treatment has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have the following symptoms because these products may make them worse. Tell your doctor immediately if you develop: persistent diarrhoea, abdominal or stomach pain/cramping, blood/mucus in your stool.