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Interferon Alfa-N3 Dosage

Medically reviewed on December 15, 2017.

Applies to the following strengths: 5000000 intl units/mL

Usual Adult Dose for Condylomata Acuminata

Refractory or recurring external condylomata acuminata: 0.05 mL (250,000 international units) per wart, injected intralesionally twice a week for up to 8 weeks

The maximum recommended dosage per treatment session is 0.5 mL (2.5 million international units).

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available

Dose Adjustments

Moderate to severe adverse experiences may require modification of the dosage regimen or, in some cases, discontinuation of interferon alfa-n3 therapy.


Interferon alfa-n3 is contraindicated in patients who have anaphylactic sensitivity to mouse immunoglobulin (IgG), egg protein, or neomycin.

Due to fever and other influenza-like symptoms associated with interferon alfa-n3 therapy, caution should be taken when administering to patients with debilitating medical conditions such as cardiovascular disease, severe pulmonary disease, or diabetes mellitus with ketoacidosis.

Patients with coagulation disorders, severe myelosuppression, or seizure disorders should receive interferon alfa-n3 with caution.

Acute, serious hypersensitivity reactions have not been reported in patients administered interferon alfa-n3. However, if such reactions develop, drug administration should be discontinued immediately and appropriate medical therapy should be instituted.

Caution is recommended if interferon alfa-n3 is to be used in fertile men. Fertile women should be encouraged to use effective contraception during treatment.

Since interferon alfa-n3 (human leukocyte derived) is made from human blood, it may carry a risk of transmitting infectious agents, e.g., viruses, and theoretically, the Creutzfeldt-Jakob disease agent.

Patients being treated with interferon alfa-n3 should be informed of the benefits and risks associated with this therapy. Since the manufacturing process, strength, and type of interferon (e.g., natural, human leukocyte interferon versus single-species recombinant interferon) may vary for different interferon formulations, changing brands may require a change in dosage. Therefore, prescribers are cautioned not to change from one interferon product to another without considering these factors.

Resolution of warts has occurred during the 3 months after treatment cessation. No further therapy (interferon alfa-n3 or conventional therapy) should be administered for 3 months after the initial 8-week course of treatment unless the warts enlarge or new warts appear. Studies to determine the safety and efficacy of a second course of treatment of warts with interferon alfa-n3 (human leukocyte derived) have not been conducted.

Safety and effectiveness have not been established in pediatric patients (less than 18 years of age).


Data not available

Other Comments

Interferon alfa-n3 is injected into the base of each wart, using a 30 gauge needle. For large warts, interferon alfa-n3 may be injected at several points around the periphery of the wart, using a total dose of 0.05 mL per wart.

The minimum effective dose for the treatment of condylomata acuminata has not been established.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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