Sweaty palms can happen for a number of reasons: nervousness; glands; illness; and stress.
Whether on a date, in a work situation, playing sports or just doing some work in the yard, sweaty hands can be embarrassing and problematic.
The following are some tips on how to keep your hands dry, even when the weather is not complying.
Remedies and Drawbacks

• Cornstarch and Talcum Powder - Some remedies involve clapping either cornstarch or talcum powder between your palms.
  There are also medicated powders sold in pharmacies that may help to soak up the moisture.
  DRAWBACKS - These types of powders do not work over the long hall, they simply provide a short term solution.
  If you need to keep your hands or feet dry for hours on end, these powders are not the answer.
  
• Deodorant? - It's true, you can use an unscented, aluminum salt based antiperspirant.
  These products are normally made specifically for hands and feet, but any particular product will do.
  DRAWBACKS - Using your hands after applying this product could be difficult, especially if you need your hands to do small specific items, such as gripping a golf club.
  
• Towel - You can go old fashioned and use a towel to keep your hands dry.
  DRAWBACKS - These are obvious, wiping your hands every five minutes can get tedious and annoying, for you and whoever you are with.
  If you are playing sports, you can't use your towel after every swing, stroke or throw.
  
• More Aluminum? - There are those who suggest that if you apply aluminum chloride paint to the area where you have persistent clamminess, it will help the problem.
  In fact, some doctors prescribe this product to patients in order to help them keep their feet dry.
  DRAWBACKS - If you are not aware of any allergies, be sure to get tested.
  You would not want to risk damaging your health with such a chemical.
  

Important Warnings Always speak with your doctor before using any product or chemical that could have a harmful or detrimental reaction.
You may not know the possible side effects of aluminum products or other anti-sweat remedies.
Your doctor may have a better sense of what products work, what products are "old wives tales" and what may actually be dangerous to apply to your skin.
People rarely invest enough time understanding how a product may affect their health, especially if the product performs as advertised.
Overall, keeping your hands dry is a challenge, but sweaty palms can be prevented if you use your head and experiment.
Talking with your doctor and with others who suffer from the malady may help you find the solution that is right for you.
There are other products out there, so ask around, go to online forums and ask others about what products might be right for you.