Your glands produce the perspiration that eventually leads to moist underarms, and moist, dark conditions create the perfect environment for bacteria to breed. When sweat and bacteria combine, underarm odor forms. The president of the American Academy of Dermatology, Dr. David Pariser, advises use of an antiperspirant applied at night, as opposed to in the morning, to control underarm odor. The use of an antiperspirant at night allows ample time for the active ingredients to seep into the pores, blocking excess perspiration.
Shower or bathe in the evening, washing your body and underarms with an antibacterial body soap. Pat your skin dry with a soft towel after washing.
Apply a thin, even layer of antiperspirant to your underarms after drying off. Slathering on a thick layer of antiperspirant has no added benefits.
Allow the antiperspirant to dry before putting on your sleepwear. Allowing the antiperspirant to dry will keep it from wiping off on clothing.
Reapply a thin, even layer of antiperspirant in the morning when you wake up. Once again, allow the antiperspirant to dry prior to dressing.
Repeat the process every evening before bed.
Do not apply an antiperspirant immediately after shaving. Wait a minimum of 24 to 48 hours after shaving to apply the antiperspirant to avoid irritation and rash.