Hexamethonium

Hexamethonium is a decamethonium-like, synthetic, peripheral nicotinic antagonist that has been used as a ganglionic blocker in hypertension. It has been largely replaced by more modern drugs and is now used only in research.

History

Hexamethonium was discovered in the early 20th century by scientists looking for a synthetic compound that could mimic the effects of acetylcholine, a neurotransmitter that transmits signals in the nervous system. The discovery of hexamethonium led to a better understanding of the autonomic nervous system and paved the way for the development of many other drugs.

Pharmacology

Hexamethonium works by blocking the effects of acetylcholine at nicotinic acetylcholine receptors in the ganglia of the autonomic nervous system. This prevents the transmission of nerve impulses through these ganglia. The drug is not selective and blocks both sympathetic and parasympathetic ganglia.

Medical uses

Hexamethonium was once used to treat conditions like hypertension, but it has been largely replaced by more modern drugs. Today, it is used primarily in research. It is also occasionally used in the treatment of severe malignant hypertension and pheochromocytoma, a rare tumor of the adrenal gland.

Side effects

The most common side effects of hexamethonium are related to its action as a ganglionic blocker. These can include dry mouth, blurred vision, and constipation. In rare cases, it can cause more serious side effects like orthostatic hypotension, a sudden drop in blood pressure when standing up.

See also

• Nicotinic antagonist
• Ganglionic blocker
• Acetylcholine