Interferon Beta 1a

Indications

Interferon Beta 1a is used for: Multiple Sclerosis

Adult Dose

Parenteral Multiple sclerosis Adult: Dose depends on the formulation used. Intramuscular 30 mcg IM qWk May be titrated using the titration kit with prefilled IM syringes starting with 7.5 mcg IM for first week, to reduce flu-like symptoms; increase by 7.5 mcg/week for next 3 weeks until recommended dose of 30 mcg/week Administration: Rotate IM injection sites between upper thighs and arms Subcutaneous 44 mcg target dose Weeks 1-2: 8.8 mcg SC 3 times/wk (at least 48 hr apart) Weeks 3-4: 22 mcg SC 3 times/wk Weeks 5+: 44 mcg SC 3 times/wk 22 mcg target dose Weeks 1-2: 4.4 mcg SC 3 times/wk (at least 48 hr apart) Weeks 3-4: 11 mcg SC 3 times/wk Weeks 5+: 22 mcg SC 3 times/wk Administration: Abdomen (except waistline), thigh, arm, buttocks

Child Dose

Safety and efficacy not established

Renal Dose

Administration

Contra Indications

Hypersensitivity to beta interferons, albumin (for albumin-containing formulations)

Precautions

Caution when used in patients with depression or psychiatric disorders, epilepsy or other CNS diseases, poorly controlled thyroid dysfunction, pulmonary disease, DM, renal or hepatic impairment, cardiac disorders, myelosuppression, auto-immune diseases, coagulation disorders, or a history of these conditions. Monitor blood counts especially in patients at high risk of myelosuppression. Eye examination should be conducted prior to starting treatment and regularly thereafter. Monitor hepatic and renal function regularly. Treatment should be discontinued in patients with chronic hepatitis who develop liver decompensation. May affect ability to drive or operate machinery. Pregnancy. Lactation: unknown; use caution

Pregnancy-Lactation

Pregnancy Category: C Lactation: unknown; use caution

Interactions

May increase the adverse effects (especially granulocytopenia) of ACE inhibitors. Increased risk of hepatic injury when used with hepatotoxic drugs. May increase serum levels of theophylline derivatives. May increase the anticoagulant effects of warfarin. May decrease the metabolism of zidovudine.

Adverse Effects

Side effects of Interferon Beta 1a : >10% Injection site reactions (83% [SC]; 28% [IM], Headache (67%), Flu-like syndrome (61%), Muscle ache (34%), Nausea (33%), URT infection (14%), Pain (24%), Fever (23%), Asthenia (21%), Diarrhea (16%), Dizziness (15%), Infection (11%), Dyspepsia (11%) 1-10% Abdominal pain (9%), Anemia (8%), Chest pain (6%) <1% Aggravation of seizure disorders

Mechanism of Action

Interferon beta 1a alters the expression and response to surface antigens and can improve immune cell activities. It has antiviral and immunomodulating properties.