Adrenoceptor Blockers

Question 1

Adrenoceptor Antagonists

Answer 1

Alpha Adrenoceptor Antagonists

Non-Selective alpha blockers

• Phenoxybenzamine
• Phentolamine

Selective Alpha 1 blocker

• Doxazosin
• Alfuzosin
• Tamsulosin

Beta Adrenoceptor Antagonists

Non-Selective B blockers

• Propranolol
• Timolol
• Pindolol

Selective B1 Blockers

• Atenolol
• Metoprolol

Alpha and Beta Adrenoceptor antagonists

• Carvedilol
• Labetalol

Mnemonic: Phony People smoke DAT PTP in the AM CLearly

Question 2

Phentolamine

Answer 2

1. Non-Selective alpha blockers

2.

3. Competitive (reversible) alpha 1, alpha 2.

alpha 1 blockade leads to decrease TPR –> decreased BP, reflex tachycardia

Question 3

Phenoxybenzamine

Answer 3

1. Non-Selective alpha blockers
2. Short term use in pheochromocytoma
3. noncompetitive (irreversible). makes covalent bond with alpha 1 receptors –> reflex tachycardia, miosis, inhibition of ejaculation

Question 4

Prazosin

Doxazosin

Terazosin

Tamsulosin

Answer 4

1. Selective alpha 1 blockers
2. Hypertension and BPH
3. Elderly syncope

Note: Less reflex tackycardia.

Tamsulosin: Buzz word: Selective alpha 1 blocker only for BPH. reduced ejaculation

Question 5

Yohimbine

Answer 5

1. Alpha 2 blockers
2. Postural hypotension and impotence

Question 6

Mirtazapine

Answer 6

1. Alpha 2 blockers
2. Depression

Question 7

Propranolol

Answer 7

1. NS Beta blocker
2. Depression (cross BBB). Increase LDL and TGs

Question 8

Acebutolol

Metaprolol

Atenolol

Answer 8

1. Cardio-selective B1 blockers

Note: Acebutolol (and Pindolol) are partial agonists (Intrinsic Sympathetic Activity) –> less bradycardia

Atenolol has no CNS entry (Nadolol too)