Drugs for heart failure ( beta 1- agonist )
Drugs:
- Dobutamine
- Dopamine
Pharmacological action:
1- heart: Dobutamine has positive inotropic and chronotropic agents on the heart muscle, such as: increasing heart rate and cardiac output, enhancing blood flow to the kidneys, which helps reduce edema and blood volume.
2- blood vessels:
A) at low doses: vasodilation
B) at very high doses: vasoconstriction
The uses:
1- It is used for a short period, especially for patients with severe heart failure who are in the hospital.
2- septic shock
3- hypotension
4- It is used for patients with low peripheral vascular resistance.
Side effect:
- Arrhythmia
- Hypertension
- Nausea
Drug interactions:
Digoxin should not be used with beta1-agonist drugs such as dobutamine because this may increase the positive inotropic effect and this may cause an abnormal increase in blood pressure.
Precautions:
The dose of dobutamine should be reduced when the drug is administered to a patient with hyperthyroidism because thyroxine increases adrenergic receptors on the heart resulting in a hypersensitive response to beta 1-agonist.
Drugs for heart failure (Phosphodiestrase inhibitors):
Amrinone and Milrinone belong to the group of phosphodiesterase inhibitors that treat heart failure, but it is not recommended to use such drugs because they may increase the death rate in patients with heart failure.
Both Amrinone and Milrinone work on positive inotropic and vasodilator action.