Page 38 - pharma 1 theoretical updated MNU_Neat

Clinical pharmacy 2024/2025 Level 3 Pharm D Pharmacology 1 (PO 502)

 Non-selective β- blockers ➔ bronchospasm in susceptible patients
Respiratory (contraindicated in bronchial asthma).
system  β1 - selective blockers are less liable to cause bronchospasm (so,

preferred in asthmatic patients): Atenolol
 Non-selective β- Blockers: augment (prolong) hypoglycemic effect of
Metabolic insulin in diabetics ➔ by blocking hepatic glycogenolysis (β2 effect)

effects
 So, β1-selective blockers are preferred in diabetics. (Atenolol)

Uses of B-blockers:

 In hypertension: β- blockers alone or in combination with diuretics ( blood volume
→  C.O.P →  BP). Inhibit renin release &angiotensin
 In angina pectoris: -ve inotropic & -ve chronotropic effects ➔  C.O.P ➔ 

myocardial oxygen consumption.
 In acute phase of myocardial infarction
 In cardiac arrhythmias

 In hyperthyroidism and thyroid storm ( T3 & T4) :(as B -blocker decrease release
of T3, T4)
 Open-angle glaucoma e.g. timolol.

 Pheochromocytoma: give both α and β- blockers.
 Treat anxiety and essential tremors (β2- effect) or non-selective
 Prophylaxis of migraine.

Contraindications: Side Effect
1) Untreated heart failure, 1) Cardiac, AV block, bradycardia, hypotension

bradycardia, heart block & 2) bronchospasm
vasospastic angina. 3) prolongation of insulin hypoglycemia
2) Bronchial asthma (only 4) cold extremities, hyperkalemia in diabetic
selective can be used) patients

3) Cold extremities (due to V.D) 5) nightmares
and gangrene. 6) mental depression especially in elderly

4) Severe depression 7) allergic reactions

| P a g e - 22 -