For at least 2 hours before or 2 hours after taking tetracycline: avoid taking iron supplements, multivitamins, calcium supplements, antacids, or laxatives.
Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.
Avoid exposure to sunlight or tanning beds. Tetracycline can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.
