In this drug factsheet:
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- increased sensitivity of skin to sunlight
- loss of appetite
- orange-yellow colour of urine
- upset stomach
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- aching joints and muscles
- difficulty swallowing
- headache (continuing)
- signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
- signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine)
- signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
- skin rash
- symptoms of anemia (such as weakness, paleness, and fatigue)
- symptoms of arthritis (such as joint pain, stiffness)
- symptoms of infection (such as fever, chills, or a general feeling of being ill)
- yellow stain to contact lenses
Stop taking the medication and seek immediate medical attention if any of the following occur:
- signs of interstitial lung disease (e.g., shortness of breath or difficulty breathing)
- signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
- signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Allergies: Some people who are allergic to furosemide, thiazide water pills, or carbonic anhydrase inhibitors also experience allergic reactions to this medication. Before you take sulfasalazine, inform your doctor about any previous adverse reactions you have had to medications, especially water pills or sulfonamide antibiotics. Contact your doctor at once if you experience signs of an allergic reaction, such as skin rash, itching, difficulty breathing or swelling of the face and throat.
Anemia: Sulfasalazine may cause low levels of red blood cells. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired or pale skin, contact your doctor as soon as possible.
Your doctor will do blood tests regularly to monitor the number of specific types of blood cells, including red blood cells, in your blood.
Asthma: Sulfasalazine can cause breathing difficulty to increase for people with asthma. If you have asthma, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Bleeding: Sulfasalazine may cause a reduced number of platelets in the blood, which can make it difficult to stop cuts from bleeding. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.
Fertility: Infertility has been observed for some men treated with sulfasalazine. Stopping the medication appears to reverse these effects.
Glucose-6-phosphate dehydrogenase enzyme deficiency: People without the G6PD enzyme should discuss with their doctor how this medication may affect the dosing and effectiveness of this medication.
Infection: Sulfasalazine can reduce the number of cells that fight infection in the body (white blood cells). Tell your doctor immediately if you notice more frequent signs of infections, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness. Your doctor will do blood tests regularly to monitor the number of specific types of blood cells in your blood.
Kidney disease: This medication can reduce kidney function. If you have kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. You will probably need to have regular tests while taking this medication to make sure that your kidneys are working properly. People who have severe kidney problems should not use this medication.
Liver disease: Sulfasalazine may reduce liver function and can cause liver failure. If you have liver disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. You will probably need to have regular liver tests while taking this medication. People with severe liver disease or very poor liver function should not take sulfasalazine.
Staining: Sulfasalazine may produce an orange-yellow colour in the urine. Similar discoloration of the skin and yellow staining of soft contact lenses have occasionally been reported.
Tablets in stool: If you notice intact enteric-coated tablets in your stool, contact your doctor.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking sulfasalazine, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: This medication is not recommended for children with juvenile rheumatoid arthritis.
What other drugs could interact with this medication?
There may be an interaction between sulfasalazine and any of the following:
- chicken pox vaccine
- diabetes medications (e.g., chlorpropamide, glipizide, glyburide, insulin, metformin, nateglinide, rosiglitazone)
- folic acid
- low molecular weight heparins (e.g., dalteparin, enoxaparin, tinzaparin)
- medications that increase sensitivity to the sun
- nitric oxide
- non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, naproxen)
- other salicylates (e.g., ASA, salsalate)
- sodium nitrite
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.