Tolazoline

Tolazoline is a non-selective competitive antagonist used primarily in the treatment of hypertension. It is a member of the class of imidazolines and is classified as a vasodilator. Tolazoline works by blocking the action of adrenergic receptors, which are involved in the regulation of blood pressure.

History[edit | edit source]

Tolazoline was first synthesized in the 1950s and was initially used as a vasoconstrictor to treat conditions such as Raynaud's disease. However, it was later found to have vasodilatory properties and was repurposed for the treatment of hypertension.

Pharmacology[edit | edit source]

Tolazoline acts as a non-selective competitive antagonist at both alpha-1 and alpha-2 adrenergic receptors. By blocking the action of these receptors, it inhibits the vasoconstrictive effect of catecholamines such as norepinephrine, leading to a decrease in blood pressure.

Clinical Use[edit | edit source]

Tolazoline is used primarily in the treatment of hypertension, particularly in patients who have not responded to other treatments. It may also be used in the treatment of pulmonary hypertension in newborns, although this use is less common.

Side Effects[edit | edit source]

Common side effects of tolazoline include hypotension, tachycardia, and flushing. Less common side effects may include nausea, vomiting, and diarrhea. In rare cases, tolazoline may cause severe hypotension or cardiac arrhythmias.