Sweaty armpits are not really condition that can be considered a disease, as it is a completely natural process of perspiration. The only difference is that the sweat glands at the armpits also secrete some substances that give off a very particular odor when it comes in contact with bacteria. This is the typical body odor that one gets familiar with, as you cross puberty. There is however, a condition called hyperhidrosis that is excessive sweating from the armpits or from any region, which sometimes requires more attention.
Hyperhidrosis is usually an acquired trait and can be triggered by any number of situations and stimuli like stress, smell, temperature, anxiety, etc. To add to this, most sufferers are usually so conscious about the problem that the anxiety before a sweat attack and during usually makes the condition worse. The usual method of controlling this condition is by using antiperspirants, and in really severe conditions, botox injections. Botox works by paralyzing the injected zone of skin and thereby inhibiting the production of sweat. At the end of it all however, hyperhidrosis may never be completely eliminated but over the course of time, this condition can be managed to such a level that at times it would seem nonexistent.
Hyperhidrosis is a condition that is not temperature specific and if the sweating that you notice does not occur in colder environments like during winter and in an air-conditioned space, then you probably do not have hyperhidrosis.
Managing excessive sweating is an arduous task especially in summers and especially if you are prone to excessive sweating. The first thing that you should try is ensure that you remove your underarm hair. This is because underarm hair can sometimes be too good an insulator of heat and removing it sometimes is a better option than keeping it. Biologically, a case can be made for keeping it stating that it allows for much freer, non-frictional movement of the arm it is sometimes a worthwhile trade-off. You would start noticing a marked improvement once you do this. In addition, also use antiperspirants and roll on deodorants. These contain substances that absorb moisture very well and can keep you dry throughout the day. To start off, you might need to make a few applications through the day but this will even out. Finally, you need to wear clothes that allow your skin to breathe better. Have you ever noticed how sometimes the sweating can sometimes cease when you are less clothed? This can be an indication that you need to wear lighter fabrics like cotton.