diuretics 2 Flashcards
MoA of Hydralazine
Increases Ca2+ release and cGMP
levels.
Acts on arteries and arterioles = vasodilation = decrease BP but reflex tachycardia
clinical uses of Hydralazine
1) Short term Tx of severe Hypertension during pregnancy.
2) Heart failure. Reduces afterload
AE of Hydralazine
°Oedema.
°Headache.
°SLE like sx.
°Reflex tachycardia
Contraindications of Hydralazine
Angina and coronary
artery disease
Beta blocker used in the management of Hypertension
Labetalol
MoA of Labetalol
B1, B2 and A1
antagonist (more
vasoconstriction)
Clinical uses of Labetalol
Hypertensive patients
with either angina,
heart failure or post MI.
AE of Labetalol
- CV depression (Bradycardia)
- fatigue,
- sexual dysfunction,
- increase LDL and triglycerides,
- bronchoconstriction.
Contraindications of Labetalol
1) Can mask hypoglycaemia sx in
diabetics.
2) Asthmatic patients
*SAFE IN PEGNANCY
α-1 blockers used in the tx of Hypertension
Doxazosin
Prazosin
Terazosin
Clinical uses of α-1 blockers
improve symptoms of BPH: Improve urine flow
AE of α-1 blockers
°Postural hypotension.
°Reflex tachycardia.
°Urinary incontinence.
°Impotence.
A2 agonists examples
Methyldopa
(decreases Bp)
MoA of Methyldopa (A2 agonist)
Less TPR and HR
clinical uses of Methyldopa
Used for Hypertension during
pregnancy
(not used anymore due to the sever AE)
AE of Methyldopa
Sedation, depression, dry mouth, less
libido, parkinsonian syndromes,
hyperprolactinaemia, bradycardia, sinus
arrest… that’s why it is not used
anymore.
Might also cause haemolytic anaemia
MoA of Nitroprusside
Releases NO -> vasodilations of arterial
and venous smooth muscles
Clinical uses of Nitroprusside
Hypertensive Emergencies (IV administration)
AE of Nitroprusside
Prolonged use may cause thiocyanate accumulation and toxicity (weakness, nausea, inhibition of thyroid function)
D1 agonists
Fenoldopam
MoA of Fenoldopam
Coronary, peripheric and splachnic vasodilation.
* Increases natriuresis, decreases bp
Clinical uses of Fenoldopam
-
Short term of severe hypertension in
hospital –> Improves renal perfusion.
(Similar effects to IV nitroprusside but lacks
thiocyanate toxicity but slower onset/offset)
Endothelin receptor
antagonists. EXAMPLES
Bosentan
Ambrisentan
Sitaxentan
-entan
MoA of Endothelin receptor
antagonists.
Antagonizes endothelin receptors =
vasodilation, proliferation inhibition
AE of Endothelin receptor
antagonists.
- Headache,
- flushing,
- hypotension.
- Hepatoxic,
- endothelins might affect the development of the cardiorespiratory system.
PDE V inhibitor
Sildenafil
MoA of Sildenafil
PD4 inhibitor -> inhibits cGMP
breakdown→pulmon
ary artery relaxation
Clinical uses of Sildenafil
°Erectile dysfunction
°Pulmonary Arterial Hypertension (PAH)
AE of Sildenafil
- Headache,
- flushing,
- dyspepsia (indigestion),
- cyanopia (blue vision).
- Risk of life-threatening hypotension in patients taking Nitrates
Contraindication of Sildenafil
patients w/ high risk of Hypotnesion
+ nitrates (will cause hypotension)