Master Nonselective Alpha-Blockers with Picmonic for Medicine

With Picmonic, facts become pictures. We've taken what the science shows - image mnemonics work - but we've boosted the effectiveness by building and associating memorable characters, interesting audio stories, and built-in quizzing.

Nonselective Alpha-Blockers

(Both α1 and α2) Nonselective Afro Block-guy
Picmonic
Phentolamine and phenoxybenzamine are drugs which lower blood pressure by inhibiting vasoconstriction through their action at α1, while also having action at α2 receptors. Phentolamine is a reversible drug which is useful in treating hypertensive crisis and is indicated for diagnosing pheochromocytomas. Phenoxybenzamine is indicated for treating pheochromocytomas, due to its slow onset and long duration of effects.Both of these medications vasodilate because of their action at α receptors, and can lead to the side effect of orthostatic hypotension. Blockade at these receptors also leads to increased sympathetic tone, which can lead to reflex tachycardia.
8 KEY FACTS
INDICATIONS
Phentolamine
Phantom-toe

Phentolamine is a reversible drug with action at both α receptors, which is used to treat hypertensive emergencies and in cases of pheochromocytoma.

Reversible
Reversed-hat

Phentolamine is reversible and dissociates from adrenergic receptors.

Pheochromocytoma (Diagnosis)
Fiat-chrome

This drug is reversible, and thus is indicated making it ideal for the diagnosis of a pheochromocytoma.

Hypertensive Crisis
Hiker-BP Crying

Phentolamine is indicated for patients on MAO inhibitors who eat tyramine-containing food, in order to treat hypertensive crisis. This drug also has use in cocaine-induced hypertension, as this drug is helpful in avoiding the unopposed alpha effects of other drugs that may be used to treat cocaine intoxication.

Phenoxybenzamine
Phantom-ox

Phenoxybenzamine is a non-selective α blocker which is non-reversible. It is often used to treat pheochromocytomas and has a slower onset and longer effect than other α blockers.

Pheochromocytoma (Treatment)
Fiat-chrome

Phenoxybenzamine is indicated for the treatment of symptoms from pheochromocytomas, which effect the adrenal gland, as this is drug has a longer effect than other α blockers.

SIDE EFFECTS
Orthostatic Hypotension
Oar Hippo-BP

As these medications inhibit α1 and α2 adrenergic receptors, they decrease vasoconstriction and vessel tone. This leads to orthostatic hypotension in patients taking these drugs.

Reflex Tachycardia
Reflex-hammer Tac-heart-card

Patients taking this medication may experience reflex tachycardia. This occurs because the hypotension and added α2 inhibition are countered physiologically by increased sympathetic tone.

Unlock all 8 facts & definitions with Picmonic Free!

JOIN FREE

Take the Nonselective Alpha-Blockers Quiz

Picmonic's rapid review multiple-choice quiz allows you to assess your knowledge.

START QUIZ NOW

It's worth every penny

Our Story Mnemonics Increase Mastery and Retention

Memorize facts with phonetic mnemonics

Unforgettable characters with concise but impactful videos (2-4 min each)

Ace Your Medical (MD/DO) Classes & Exams with Picmonic:

Over 870,000 students use Picmonic’s picture mnemonics to improve knowledge, retention, and exam performance.

Choose the #1 Medical (MD/DO) student study app.

Picmonic for Medicine (MD/DO) covers information that is relevant to your entire Medical (MD/DO) education. Whether you’re studying for your classes or getting ready to conquer the USMLE Step 1, USMLE Step 2 CK, COMLEX Level 1, or COMLEX Level 2, we’re here to help.

Works better than traditional Medical (MD/DO) flashcards.

Research shows that students who use Picmonic see a 331% improvement in memory retention and a 50% improvement in test scores.