Tetracycline (Sumycin) is an antibiotic.

Use Tetracycline (Sumycin) as directed by your doctor.

Take Tetracycline (Sumycin) by mouth on an empty stomach at least 1 hour before or 2 hours after eating.

If you also take antacids containing aluminum, calcium, or magnesium; preparations containing bismuth, iron, zinc, or sodium bicarbonate; or calcium rich foods, do not take them within 2 to 3 hours before or after taking Tetracycline (Sumycin).

Check with your doctor if you have questions.

Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Black hairy tongue; blurred vision; bulky loose stools; diarrhea; difficulty swallowing; fever; headache; hives; hoarseness; indigestion; inflammation or redness of tongue; joint pain; loss of appetite; mouth sores; nausea; rash; sensitivity to sunlight; sore throat; stomach pain; swelling and itching of the rectum.

Seek medical attention right away if any of these SEVERE side effects occur:
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); infection (fever, chills, sore throat); itching; nausea; severe skin reaction to the sun; vaginal irritation or discharge; vomiting.

This is not a complete list of all side effects that may occur. If you have questions or need medical advice about side effects, contact your doctor or health care provider.

Tell your health care provider if you are taking any other medicines, especially any of the following:

Acitretin or isotretinoin because side effects, such as increased pressure in the fluid surrounding the brain, may occur

Digoxin, methotrexate, methoxyflurane, or oral anticoagulants (eg, warfarin) because the risk of their side effects may be increased by Tetracycline (Sumycin)

Atovaquone, lithium, oral contraceptives (birth control pills), or penicillins (eg, amoxicillin) because their effectiveness may be decreased by Tetracycline (Sumycin)

This may not be a complete list of all interactions that may occur. Ask your health care provider if Tetracycline (Sumycin) may interact with other medicines that you take.

If overdose is suspected, contact your local poison control center or emergency room immediately.

Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

if you are pregnant, planning to become pregnant, or are breast-feeding

if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement

if you have allergies to medicines, foods, or other substances

if you have diarrhea, a stomach infection, or kidney problems

Do not double doses to make up for a missed dose.

Tetracycline (Sumycin) works by slowing the growth of sensitive bacteria by interfering with the production of proteins needed by the bacteria to grow.

Slowing the bacteria's growth allows the body's defense mechanisms to destroy them.

Ask your doctor or pharmacist for more information.

Store away from heat and direct light.

Keep the medicine from freezing.

Contact your doctor right away if stomach pain or cramps, severe diarrhea, or bloody stools occur.

Hormonal birth control may not work as well while you are using Tetracycline (Sumycin). To prevent pregnancy, use an extra form of birth control.

If you have any questions about Tetracycline (Sumycin), please talk with your doctor, pharmacist, or other health care provider.