While they were more effective than topical applications of benzoyl peroxide, the bacteria eventually grew resistant to the antibiotics and the treatments became less and less effective.Also, antibiotics had more side effects than topical applications, such as stomach cramps and severe discoloration of teeth.

Before applying them the patient needs to wash his or her face with warm water and dry. Severe acne usually indicates the necessity of prescription medication to treat the pimples.

Prescription medications used to treat acne and pimples include isotretinoin, which is a retinoid.

Historically, antibiotics such as tetracyclines and erythromycin were prescribed.

Inside the pore are sebaceous glands which produce sebum.

When the outer layers of skin shed (as they do continuously), the dead skin cells left behind may become 'glued' together by the sebum.

This causes the blockage in the pore, especially when the skin becomes thicker at puberty.The sebaceous glands produce more sebum which builds up behind the blockage, and this sebum harbours various bacteria including the species Propionibacterium acnes, causing infection and inflammation.In simpler terms, oil is in your skin and may clog up glands in your skin.This results in pimples, zits or acne, mostly during puberty.Common over-the-counter medications for pimples are benzoyl peroxide and/or salicylic acid and antibacterial agents such as triclosan.Both medications can be found in many creams and gels used to treat acne (acne vulgaris) through topical application. A regimen of keeping the affected skin area clean plus the regular application of these topical medications is usually enough to keep acne under control, if not at bay altogether.