Question

Atropine (an anti-cholinergic medication) blocks muscarinic receptors. Which of the following symptoms would you expect to see in a patient who is not in homeostasis because of an excessive atropine dose? (more than one answer possible—circle all that apply)

1. decrease in salivation
2. increase in sweating
3. decrease in motility of digestive tract
4. dilation of pupil of eye
5. increase in lacrimation (tear production in eye)
6. decrease in heart rate
7. urinary retention

Answer 1

Atropine blocks the muscarinic receptors and antagonises all the activities of Ach on muscarinic receptors.

Decrease in salivation and makes the mouth dry

Decrease in sweating and makes the skin dry and hot

Decrease in motility of digestive tract and partly secretion of gastric acids

Causes dilation of pupil (mydriasis)

Decreases lacrymal secretions

Higher doses of atropine cause progressive tachycardia by blocking M2 receptors on the SA node.

Increase urinary retention by inhibiting contractions and tone of bladder