Question: I have terrible underarm odor regardless of what deodorant I use. One female dermatologist gave me erythromycin roll on, but to no avail. Please help me find an answer.

Dr. Hibberd's Answer:
Underarm odor usually occurs in association with blockage of the apocrine sweat ducts in the armpit area, and with mild local bacterial overgrowth. Bacteria and other organisms may also inflame barely visible nodules.
Treatment with the antibiotic clindamycin is often effective, though some patients need high dose tetracycline or erythromycin until visible lesions resolve. Isotretoin is also useful for some patients. Persistent nodules require drainage or excision.
Excessive perspiration should be controlled with topical agents such as aluminum chloride solution, water-based for mild cases and alcohol-based for more severe cases. Local Botox injections have also been used with reported success, though at a high price. Botulinum toxin inhibits sweating for about five months depending upon the amount used.
Be sure to reduce your intake of spices that may aggravate body odor, such as garlic, and avoid the use of close-fitting synthetic materials that trap heat and encourage perspiration. Loose-fitting cotton materials that breathe well are probably best.