Underarm filiform warts can be treated with ointment such as retinoic acid ointment and recombinant human interferon alpha 2b cream under the guidance of a doctor. 1. Vitamin A acid ointment can be used for filiform warts under the guidance of a doctor for keratosis pilaris, which is contraindicated for those who are allergic to the drug, pregnant women, and patients with dermatitis and eczema, and can cause adverse reactions such as erythema, swelling, flaking, scabbing, and pigmentation increases or decreases. 2. Recombinant human interferon α2b cream: under the guidance of a doctor can be used for warts caused by human papillomavirus disease, this drug is contraindicated for those who are allergic to it, may cause allergies, irritation and other adverse reactions. If you have any kind of underarm filiform warts, it is advisable to go to the hospital in time and use the medication under the doctor’s guidance.