Pharmacology: antihypertensives (minor drugs) Flashcards
Other drugs used to treat hypertension?
SNS inhibitors: beta blockers, alpha 1 antagonists, alpha 2 receptor and imidazoline antagoinsts, alpha 2 receptor agonist
Other vasodilations
BETA BLOCKERS
MOA?
Reduce sympathetic drive to the heart - decreased HR, TPR (vasodialtion, CO –> hence MAP (treats hypertension)
Inhibits renin release –> reduced BP/treats hypertension
Lipid soluble beta blockers can enter the brain, and reduce sympathetic outflow from the CNS
BETA BLOCKERS
Are they first line in uncomplicated, essential hypertension? Why/why not?
No - due to their ADRs
BETA BLOCKERS
Indications in addition to hypertension?
Angina
Post MI
Dysrhythmias
Heart failure …
BETA BLOCKERS
Suffix, and examples?
-lol; metoprolol, atenolol, propranolol, carvedilol
ALPHA 1 ANTAGONISTS
MOA?
Example?
Blocks A1 adrenoceptors in vascular SMCs - vasodilation of SMCs
Prazosin
ALPHA 2 RECEPTOR AND IMIDAZOLINE AGONISTS
MOA?
Reduce CNS sympathetic outflow –> vasodilation
ALPHA 2 RECEPTOR AND IMIDAZOLINE AGONISTS
ADRs?
Sedation, depression, fatigue
Rebound hypertension upon withdrawal
ALPHA 2 RECEPTOR AND IMIDAZOLINE AGONISTS
Two examples?
Their uses?
Moxonidine and clonidine
- Moxonidine is becoming popular as a 3rd/4th line treatment for HT
Clonidine is not often used. Mainly now just used for HT in pregnancy and emergency control of HT
ALPHA 2 RECEPTOR AGONIST
Example?
MOA?
Methyldopa
Forms a false NT, reducing NA synthesis
ALPHA 2 RECEPTOR AGONIST
ADRs?
Liver dysfunction
Sedation
ALPHA 2 RECEPTOR AGONIST
How often does it need to be taken?
Is its use limited in pregnancy?
2-4x a day
Yes
OTHER VASODILATIORS
Do they predominantly dilate arteries or veins?
Are they frequently used? What are some examples in which they’re used?
Arterial
No. In HT emergencies and refractory HT
OTHER VASODILATORS
Examples?
hydralazine, minoxidil, sodium nitroprusside
