This document discusses several classes of drugs that act on the autonomic nervous system and neuromuscular junction. It describes drugs that act as agonists or antagonists at adrenergic and cholinergic receptors in the sympathetic and parasympathetic nervous systems. It also discusses drugs that affect the release or reuptake of neurotransmitters, as well as ganglionic blocking drugs that inhibit transmission between pre- and postganglionic neurons. Finally, it summarizes drugs that enhance or block transmission at the neuromuscular junction.