What are common anticholinergic reactions?

Anticholinergic reactions are associated with the blockade of acetylcholine in the nervous system, which leads to various physiological effects. Increased body temperature and dilated pupils are hallmark signs of anticholinergic effects.

When the anticholinergic mechanisms are in play, there is reduced secretions from sweat glands, which can lead to decreased ability to regulate body temperature, thus causing increased body temperature. Additionally, the dilation of pupils, or mydriasis, occurs due to the relaxation of the muscle controlling the iris, influenced by anticholinergic activity blocking the parasympathetic nervous system.

While other listed reactions like headaches, dizziness, nausea, vomiting, and dry skin can occur with various medical conditions or medications, they are not as definitive in identifying an anticholinergic reaction as the increase in body temperature and pupil dilation. This makes the correct answer particularly relevant when recognizing the classic signs of anticholinergic syndrome.