Armpit breakouts are caused by infection or blockage in the hair follicles of the armpit. Common culprits include waxing, shaving, plucking, and wearing tight clothes. In addition, products like deodorant may also lead to irritation or contact dermatitis, which can result in redness, bumps, and itching. Fortunately, simple lifestyle changes can decrease the likelihood of getting breakouts under your arms. Here are some tips: (1) Wear loose clothing to avoid rubbing in the area. (2) Avoid dry-shaving and if you're in the shower, wait several minutes before beginning to shave to soften the hair follicle. (3) When shaving, move your razor in the direction of hair growth. (4) Change your razor often. If you experience irritation after shaving, apply a warm compress to the area and discuss topical options with your dermatologist if bumps and inflammation persist.