Non selective Alfa and Beta receptor agonist (dopamine ) pharmacological action , uses , side effect and contraindication .
Ph. Action of Dopamine
- · Pharmacological action on heart :
- we talked about the location of the beta 1 receptors of the heart . the dopamine have stimulatory effect of these receptor on heart muscle causing increase in heart rate , cardiac output , cardiac contractility , positive inotropic and positive chronotrope effect . ( at low dose )
- · Pharmacological action on blood vessels :
- it is found Alfa 1 receptors affecting by high doses , lead to vasoconstriction and increase systemic blood pressure . at low doses doing as vasodilator and decrease blood pressure .
- · Pharmacological action on kidney :
- the mechanism of action is to reverse the blood vessel throughout the body . dilate renal and arterioles vessel around the digestive system , by stimulat receptors named D1 and D2 not alfa , beta receptors .
Uses of Dopamine :
- · Treats heart failure and cardiogenic and septic shock .
- · Sever heart disease .
- · The norepinephrine has reduce effect blood supply and cause shutdown of renal function , in contrast dopamine . so dopamine is preferred
- · When the kidneys are unable to form urine and filtration .
Sid effect of dopamine :
High blood pressure and increase in heart rate , tachycardia
, hyperactivity in life style , consciousness , sleeping disturbance and rarely
headache , dry mouth , digestive problem , consti . most likely all side
effects will be repeated on non selective drugs .
Contraindication of dopamine :
- · It should be avoided by breastfeeding women , pregnant .
- · we can not used longer duration for relief symptoms .
- · Hallucinations patient .
- · The adrenergic neuron in presynaptic has dopamine receptor so , it will affect the performance of norepinephrine , epinephrine and acetyl choline action release and reuptake . act as Alfa 2 antagonist .
- Oliguria : dopamine is the choice to treat which meaning weakness in kidney function .