 [ Symptoms ] i take atenolol flecainide hydrochlorothiazide prednisone and warfarin do any of them cause thinning hair [ Disease ] if overdose is suspected contact your local poison control center or emergency room immediately us residents can call the us national poison hotline at 1 800 222 1222 canada residents can call a provincial poison control center symptoms of overdose may include agitation severe vomiting extreme thirst ringing in the ears increased sweating fainting chest pain fastirregular heartbeat seizures