Some medical conditions may interact with Azulfidine. 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 liver or kidney problems, asthma, severe allergies, blood problems (eg, anemia, low white blood cell levels), or rheumatoid arthritis
• if you have glucose-6-phosphate dehydrogenase deficiency
• if you have an infection (eg, strep throat) 

Some MEDICINES MAY INTERACT with Azulfidine. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Anticoagulants (eg, warfarin) or methotrexate because the risk of their side effects may be increased by Azulfidine
• Beta-blockers (eg, propranolol), digoxin, or folic acid because their effectiveness may be decreased by Azulfidine
• Methenamine because the risk of crystals in the urine may be increased
  
  This may not be a complete list of all interactions that may occur.

Azulfidine may cause drowsiness or dizziness. These effects may be worse if you take it with alcohol or certain medicines. Use Azulfidine with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
Azulfidine may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to Azulfidine. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
Azulfidine may discolor the urine or skin an orange-yellow color. This is normal and not a cause for concern.
Contact your doctor if you develop sore throat, fever, unusually pale skin, dark urine, pale stools, persistent stomach pain or loss of appetite, yellowing of the skin or eyes, or unusual bruising or bleeding. Contact your doctor if you have yellowing of the skin along with dark urine, pale stools, or persistent stomach pain or loss of appetite. These could be signs of a serious side effect.
Some men taking Azulfidine have developed a decreased number of sperm and infertility. These effects usually went away after Azulfidine was stopped. Discuss any questions or concerns with your doctor.
Lab tests, including liver function, kidney function, complete blood cell counts, or urine tests, may be performed while you use Azulfidine. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
Use Azulfidine with caution in the ELDERLY; they may be more sensitive to its effects.
Azulfidine should not be used in CHILDREN younger than 2 years old; safety and effectiveness in these children have not been confirmed.
Use Azulfidine with extreme caution in CHILDREN younger than 10 years old who have diarrhea or an infection of the stomach or bowel.
PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Azulfidine while you are pregnant. Azulfidine is found in breast milk. If you are or will be breast-feeding while you use Azulfidine, check with your doctor. Discuss any possible risks to your baby.

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Headache; loss of appetite; mild stomach upset or pain; nausea; vomiting.
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); bloody diarrhea; bluish discoloration of the skin or nails; chest pain; dark urine; decreased urination; fever, chills, or sore throat; hearing loss; mental or mood changes; muscle pain; numbness or tingling in the fingers or toes; pale stools; persistent loss of appetite; pinpoint bruises; red, swollen, peeling, or blistered skin; seizures; severe or persistent dizziness, drowsiness, headache, or trouble sleeping; severe or persistent stomach pain; shortness of breath; trouble walking; unusual bruising or bleeding; unusual tiredness or weakness; unusually pale skin; yellowing of the eyes; yellowing of the skin along with dark urine, pale stools, or persistent loss of appetite.

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