Do not drink alcohol while you are taking this medication and for at least 1 day after you stop taking it. You may have unpleasant side effects such as fast heartbeats, warmth or redness under your skin, tingly feeling, nausea, and vomiting.

Check the labels of any medicines or food products you use to make sure they do not contain alcohol.

Avoid taking this medication with milk or other dairy products. Also avoid taking iron supplements, multivitamins, calcium supplements, or antacids. These products can make it harder for your body to absorb tetracycline.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

Avoid exposure to sunlight or artificial UV rays (sunlamps or tanning beds). Tetracycline can make your skin more sensitive to sunlight and sunburn may result. Use a sunscreen (minimum SPF 15) and wear protective clothing if you must be out in the sun.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

• diarrhea that is watery or bloody;

• seizures (convulsions);

• numbness, burning, pain, or tingly feeling in your hands or feet;

• burning or irritation in your throat, chest, or upper stomach;

• fever, chills, body aches, flu symptoms;

• easy bruising or bleeding, unusual weakness; or

• nausea, stomach pain, loss of appetite, itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

• stomach pain;

• nausea, upset stomach;

• headache;

• dizziness;

• white patches or sores inside your mouth or on your lips;

• metallic taste in your mouth; or

• vaginal itching or discharge.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

The following drugs can interact with bismuth subcitrate potassium, metronidazole, and tetracycline. Tell your doctor if you are using any of these:

• cimetidine (Tagamet);

• lithium (Lithobid, Eskalith, others);

• a blood thinner such as warfarin (Coumadin);

• seizure medication such as phenytoin (Dilantin) or phenobarbital (Luminal, Solfoton); or

• a penicillin antibiotic such as amoxicillin (Amoxil, Trimox, others), penicillin (BeePen-VK, Pen-Vee K, Veetids, others), dicloxacillin (Dynapen), carbenicillin (Geocillin), oxacillin (Bactocill), and others.

This list is not complete and there may be other drugs that can interact with bismuth subcitrate potassium, metronidazole, and tetracycline. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.

Your pharmacist can provide more information about bismuth subcitrate potassium, metronidazole, and tetracycline.