Its action on the neuronal nicotinic receptors is primarily through the block of the ion pore, rather than through competition with the binding site for acetylcholine.

[3] Postganglionic sympathetic systems are usually regulated by norepinephrine (noradrenaline) (adrenergic receptors), whereas parasympathetic systems are acetylcholine-based, and instead rely on muscarinic receptors (some post-ganglionic sympathetic neurons, such as those stimulating sweat glands, release acetylcholine).

The organ system and adverse effects of ganglion blockers are due to the parasympathetic and sympathetic stimuli blockage at preganglionic sites.

Side-effects include combined sympatholytic (e.g., orthostatic hypotension and sexual dysfunction) and parasympatholytic (e.g., constipation, urinary retention, glaucoma, blurry vision, decreased lacrimal gland secretion, dry mouth (xerostomia)) effects.

[4] The use of inhaled hexamethonium, an unapproved drug, in a normal volunteer during a medical study is believed to have caused or contributed to her death[5][6] in light of the presence of abnormal "ground glass opacities" on her chest X-ray.