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(nitisinone) Capsules and Oral Suspension 4 mg/mL


ORFADIN contains nitisinone, which is a hydroxyphenyl-pyruvate dioxygenase inhibitor indicated as an adjunct to dietary restriction of tyrosine and phenylalanine in the treatment of hereditary tyrosinemia type 1 (HT-1).

Nitisinone occurs as white to yellowish-white, crystalline powder. It is practically insoluble in water, soluble in 2M sodium hydroxide and in methanol, and sparingly soluble in alcohol.

Chemically, nitisinone is 2-(2-nitro-4-trifluoromethylbenzoyl) cyclohexane-1,3-dione, and the structural formula is:

Figure 1: The molecular formula is C14H10F3NO5 with a relative mass of 329.23

ORFADIN® (nitisinone) Figure 1 Illustration

Capsules: Hard, white-opaque capsule, marked as 2 mg, 5 mg, 10 mg or 20 mg strengths of nitisinone, intended for oral administration. Each capsule contains 2 mg, 5 mg, 10 mg or 20 mg nitisinone, plus pre-gelatinized starch. The capsule shell is gelatin and titanium dioxide and the imprint is an iron oxide.

Oral suspension: 4 mg/mL, a white, slightly viscous opaque suspension. The inactive ingredients are hydroxypropyl methylcellulose, glycerol, polysorbate 80, sodium benzoate, citric acid monohydrate, trisodium citrate dihydrate, strawberry aroma (artificial) and purified water.

Glycerol: Each mL contains 500 mg.

Sodium: Each mL contains 0.7 mg (0.03 mEq).

What are the possible side effects of nitisinone (Orfadin)?

Stop using nitisinone and get emergency medical help if you have any of these serious side side effects. Some of these side effects can be caused by the medication or by your diet:

  • an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);
  • jaundice (yellowing of the skin or eyes);
  • eye redness, pain, burning, or sensitivity to light;
  • vision changes;
  • bloody or black stools; or
  • unusual bruising or bleeding.

Other, less serious side effects may be more likely to occur....

Read All Potential Side Effects and See Pictures of Orfadin »

What are the precautions when taking nitisinone capsules and oral suspension (Orfadin)?

Before giving nitisinone, tell the doctor or pharmacist if your child is allergic to it; or if your child has any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell the doctor or pharmacist your child's medical history, especially of: eye problems (such as cataracts, corneal ulcers).

Patients taking this medication are at risk for developing high levels of tyrosine in the blood, possibly leading to eye, skin, and nervous system problems. (See Side effects section.) To decrease the risk of high tyrosine levels, patients should follow a diet low in tyrosine and phenylalanine. Avoid foods and beverages that contain aspartame or are...

Read All Potential Precautions of Orfadin »

Last reviewed on RxList: 11/14/2016
This monograph has been modified to include the generic and brand name in many instances.

Report Problems to the Food and Drug Administration


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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