For the treatment of 

• Crohn's disease
• Rheumatoid arthritis (as a second-line agent)

Crohn's Disease

Rheumatoid Arthritis

Adults: 3 to 4 g daily in equally divided doses with no more than an eight-hour delay between doses. To lessen the risk of gastrointestinal intolerance, it is sometimes preferable to start therapy with a lower dose, such as 1 to 2 g daily. If daily doses greater than 4 g are required to obtain desired benefits, keep in mind the increased risk of toxicity. Children aged six and up: 40 to 60 mg/kg body weight divided into three to six doses during a 24-hour period.

Maintenance Therapy:

• Adults:  2 g daily.
• Children six years of age and older:  30 mg/kg body weight in each 24-hour period, divided into 4 doses. 

Commonly associated side effects include-

• Fever
• sore throat
• eye irritation
• Allergies
• swollen glands
• muscle aches
• severe weakness

Fever

Pharyngitis

Eye Irritation

Myalgia

• Follow doctor's instructions about any restrictions on food, beverages, or activity.
• Taking sulfasalazine can make it harder for your body to absorb folic acid, and folic acid helps prevent major birth defects of the baby's brain or spine. One may need to take folic acid supplements if one takes sulfasalazine during pregnancy.
• If he/she has porphyria, a blockage in the bladder or intestines, or if he/she is  allergic to sulfa medications, aspirin, or other salicylate-like medicines, he/she  should avoid taking sulfasalazine.