Medically, the condition of having excessively sweaty palms is known as “Palmar Hyperhidrosis”. In general, it can be caused by two different things- emotional stress and the result of your body trying to control its temperature (thermoregulation). In the case of being excited, scared, or nervous, the cause is stimulation of a specific type of sweat gland from your fight or flight (sympathetic) nervous system. To understand why, let’s talk about the different types of sweat glands and what causes all that moisture.