What are the effects and side effects of atropine?

Under normal circumstances, common formulations of atropine include injections and tablets. Atropine has effects such as anticholinergic action, smooth muscle relaxation, secretion inhibition, increased heart rate, and pupil dilation; its side effects include dry mouth, blurred vision, urinary retention, constipation, and increased heart rate. It should be used strictly according to medical instructions. A detailed analysis is as follows:

I. Effects

1. Anticholinergic effect: Atropine blocks cholinergic nerve transmission and inhibits cholinergic excitatory effects. This property makes atropine commonly used to regulate certain physiological functions.

2. Smooth muscle relaxation: Atropine can relax smooth muscles. For example, in the gastrointestinal tract, it can relieve spasms of intestinal smooth muscles and alleviate spastic pain associated with gastrointestinal disorders.

3. Secretion inhibition: Atropine reduces secretions from the salivary glands, gastric juice, pancreatic juice, and other glands.

4. Increased heart rate: Atropine stimulates sympathetic nervous activity in the heart, leading to an increased heart rate. Therefore, atropine is sometimes used in the treatment of bradycardia (abnormally slow heart rate).

5. Pupil dilation: Atropine causes pupil enlargement, known as mydriasis. It is used in ophthalmic examinations or treatments to widen the visual field and facilitate fundus examination.

II. Side Effects

1. Dry mouth: One of the common side effects of atropine is dryness of the mouth and throat due to inhibition of salivary gland secretion.

2. Blurred vision: Atropine-induced pupil dilation may lead to blurred vision. This effect is usually temporary but may cause discomfort during tasks requiring near vision.

3. Urinary retention: Atropine may cause urinary retention, manifesting as difficulty urinating or incomplete bladder emptying, due to its relaxing effect on the urinary sphincter.

4. Constipation: By inhibiting contractions of gastrointestinal smooth muscles, atropine may slow intestinal motility, delay food transit through the gut, and result in constipation.

5. Increased heart rate: Atropine stimulates cardiac sympathetic nerves and accelerates heart rate, which may have adverse effects in patients with pre-existing heart conditions or hypertension.

Atropine should be used under the guidance of a physician or pharmacist, with careful attention to potential side effects and safety considerations.