The smell or odour from sweaty armpits can be due to two things- excessive sweat and bacteria. This is derived from the eccrine glands or sweat glands present in large numbers under the armpits, on the hands, feet, and face. miraDry can definitely reduce the amount of sweating, and hence the amount of bacteria on your skin.
The second cause of smelly armpits is due to apocrine glands. These glands are also present in large numbers in the underarms. Unfortunately treatments such as antiperspirants, Botox, and even miraDry will not effectively eliminate apocrine glands. If smelling is due to bacteria residing in these glands, you may still smell, but you will sweat less following miraDry.