Drug information of Dopamine

Mechanism of effect

Dopamine is a precursor to norepinephrine in noradrenergic nerves and is also a neurotransmitter in certain areas of the central nervous system. Dopamine produces positive chronotropic and inotropic effects on the myocardium, resulting in increased heart rate and cardiac contractility.

 This is accomplished directly by exerting an agonist action on beta-adrenoceptors and indirectly by causing release of norepinephrine from storage sites in sympathetic nerve endings. In the brain, dopamine acts as an agonist to the five dopamine receptor subtypes (D1, D2, D3, D4, D5).

Pharmacodynamic

Endogenous catecholamine, acting on both dopaminergic and adrenergic neurons.

Low dose stimulates mainly dopaminergic receptors, producing renal and mesenteric vasodilation;

higher dose stimulates both beta1-adrenergic and dopaminergic receptors, producing cardiac stimulation and renal vasodilation; large dose stimulates alpha-adrenergic receptors

Pharmacokinetics

Absorption

Onset: 5 min (adults)

Duration: <10 min

Distribution

Vd: 1.8-2.45 L/kg

Metabolism

Metabolized in liver, kidney, and plasma by monoamine oxidase and catechol-O-methyl transferase

Metabolites: Norepinephrine (active), inactive metabolites

Elimination

Half-life: 2 min

Total body clearance: 115 mL/kg/min

Excretion: Urine (80%)

Drug indications

renal failure , Congestive heart failure

Dosage

Ampoule

DOPAMINE HCL 200MG/5ML

**Adults:

• Bradyarrhythmia, acute symptomatic

2 to 10 mcg/kg/min IV, titrate to response

• Cardiac arrest - Hypotension, acute

5 to 10 mcg/kg/min IV, titrate to response

• Cardiogenic shock

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; MAX 50 mcg/kg/min IV

• Congestive heart failure

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; MAX 50 mcg/kg/min IV

• Decreased cardiac output

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; MAX 50 mcg/kg/min IV

• Renal Failure

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; MAX 50 mcg/kg/min IV

• Septic shock

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; MAX 50 mcg/kg/min IV

• Shock, due to MI, trauma, or open heart surgery

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; MAX 50 mcg/kg/min IV  

**Pediatrics:

• Important Note:

Orphan drug designation: Prevention of intraventicular hemorrhage in hypotensive premature neonates.

• General Dosage Information:

Not FDA approved in children.

• Cardiac arrest-Hypotension, acute

2 to 20 mcg/kg/min IV/Intraosseous; titrate to response

• Hypotension, acute

Initial, 2 to 5 mcg/kg/min IV; increase in 5 to 10 mcg/kg/min increments; Max 30 mcg/kg/min IV

Side effects

Anxiety , Headache , nausea , Tachycardia , vomiting , Injection-site reaction , ventricular arrhythmias , oliguria , shortness of breath , Pupillary Dilation

Interactions

Oxybutynin , Phenytoin , Haloperidol , isocarboxazid , protriptyline , Droperidol , Tolazoline , Doxapram , Paliperidone , Cariprazine , Blonanserin , Chlorprothixene

Alerts

May cause peripheral ischemia in patients with history of occlusive vascular disease. If ischemia occurs, prevent sloughing and necrosis in ischemic areas by infiltrating areas as soon as possible with 5-10 mg of phentolamine (adrenergic blocking agent) in 10-15 mL of saline solution.

Cautions

Use caution in angina pectoris, extravasation, hypovolemia, occlusive vascular disease, ventricular arrhythmias, recent use of monoamine oxidase inhibitors, sensitivity to sulfites

Drug is inactivated by alkali

May cause increases in heart rate

Use with caution after myocardial infarction

Monitor blood pressure closely

Use caution in patients taking MAO inhibitors; prolong hypertension may occur with concurrent use

Points of recommendation

• Instruct patient to report signs/symptoms of extravasation, as drug is caustic.
• Dopamine may cause nausea, vomiting, headache, anxiety,oliguria, or dyspnea.

Advice patient to report signs/symptoms of angina, palpitations, or tachyarrhythmia

Pregnancy level

C

Related drugs

Dobutamine , Domperidone , Metaraminol Tartrate