Final answer:
Parasympathetic drugs can enhance or inhibit the effects of the parasympathetic nervous system. These drugs are referred to as parasympathomimetic or anticholinergic drugs. Similarly, sympathomimetic drugs mimic the actions of adrenergic molecules, while sympatholytic drugs block adrenergic activity.
Step-by-step explanation:
Parasympathetic drugs can either enhance or inhibit the effects of the parasympathetic nervous system.
Drugs that enhance cholinergic effects are called parasympathomimetic drugs, while drugs that inhibit cholinergic effects are called anticholinergic drugs.
Parasympathetic drugs can also have indirect effects on the cholinergic system.
In contrast, drugs that affect the sympathetic system are called sympathomimetic drugs if they mimic the actions of adrenergic molecules and stimulate target organs.
Conversely, drugs that block adrenergic activity and cancel the sympathetic influence on the target organ are called sympatholytic drugs.