Methods for treatment of hyperhidrosis, Raynaud's phenomenon, cerebral ischemia and asthma and hypertension by nerve stimulation are disclosed. In particular, the invention relates to the improvement of these conditions by stimulating at least one ganglion selected from the group consisting of T-1 through T-4 ganglia, cervical ganglia, renal nerve or combinations thereof with an implantable, wireless, battery-less and lead-less stimulator. Stimulations of the ganglion may be carried out with pulsed radiofrequency, thermal energy or optical irradiation.