Introduction
Myomine is a medicine used for the treatment of low blood pressure due to heart attack, infection, heart surgery, or trauma. It is also useful in heart failure. It increases the blood pressure by increasing pumping capacity of the heart and improving blood flow in the body.
Myomine also improves urine output and may help to prevent kidney failure in critically ill patients. It is administered under the supervision of a doctor as it requires continuous blood pressure monitoring. The dose has to be individually adjusted as per the patient's response to the therapy. You should continue all your other medicines that are advised by the doctor for your long-term treatment even after this injection. Your doctor may advise for regular monitoring of blood pressure.
Side effects of this medicine include palpitations, tachycardia (increased heart rate), and headache. You must inform the doctor if you are suffering from any liver or kidney disease. Also, let your doctor know about all the other medications that you are using regularly.
Uses of Myomine
- Heart failure
- Low blood pressure
Side effects of Myomine
Common
- Flushing (sense of warmth in the face, ears, neck and trunk)
- Headache
- Increased heart rate
- Palpitations
How to use Myomine
Your doctor or nurse will give you this medicine. Kindly do not self administer.
How Myomine works
Myomine is a sympathomimetic agonist. It works on the receptors in the kidney, gut, brain and heart thereby relaxing the blood vessels in these organs. This restores the poor blood supply and oxygen delivery to these organs. It also causes an increase in urine production in the kidneys and protects them from injury.
What if you forget to take Myomine?
If you miss a dose of Myomine, please consult your doctor.
Indication
Shock, Acute heart failure, Hypotension
Adult Dose
Hemodynamic Conditions
Treatment of hypotension, low cardiac output, poor perfusion of vital organs; used to increase mean arterial pressure in septic shock patients who remain hypotensive after adequate volume expansion
1-5 mcg/kg/min IV (low dose): May increase urine output and renal blood flow
5-15 mcg/kg/min IV (medium dose): May increase renal blood flow, cardiac output, heart rate, and cardiac contractitlity
20-50 mcg/kg/min IV (high dose): May increase blood pressure and stimulate vasoconstriction; may not have a beneficial effect in blood pressure; may increase risk of tachyarrhythmias
May increase infusion by 1-4 mcg/kg/min at 10-30 min intervals until optimum response obtained
Titrate to desired response
Child Dose
Hemodynamic Conditions
Treatment of hypotension
1-5 mcg/kg/min IV, increased to 5-20 mcg/kg/min; not to exceed 50 mcg/kg/min
Titrate to desired response
Contraindication
Pheochromocytoma, uncorrected tachyarrhythmias, ventricular fibrillation. Hypersensitivity.
Mode of Action
Dopamine stimulates dopaminergic receptors at lower doses producing renal and mesenteric vasodilation while at higher doses stimulate both dopaminergic and ?-adrenergic receptors producing cardiac stimulation and renal vasodilation. It increases heart rate and force of contraction. At low infusion rates vasodilatation occurs in the renal, mesenteric, coronary and cerebral beds. At higher rates vasoconstriction in skeletal muscles and a rise in BP.
Precaution
Shock secondary to MI, history of peripheral vascular disease. Correct hypovolaemia before infusion. History of occlusive vascular disease e.g, atherosclerosis, Raynaud's disease, Buerger's disease, diabetic endarteritis; disproportionate increase in diastolic pressure. Pregnancy.
Lactation: Unknown whether drug is excreted into breast milk; use caution
Side Effect
Cardiovascular: Ventricular arrhythmia, atrial fibrillation (at very high doses), ectopic beats, tachycardia, anginal pain, palpitation, cardiac conduction abnormalities, widened QRS complex, bradycardia, hypotension, hypertension, vasoconstriction
Respiratory: Dyspnea
Gastrointestinal: Nausea, vomiting
Metabolic/nutritional: Azotemia
Central nervous system: Headache, anxiety
Endocrine: Piloerection
Ocular: Increased intraocular pressure; dilated pupils
Gangrene of extremities has occurred when high doses were administered for prolonged periods or in patients with occlusive vascular disease receiving low doses of dopamine hydrochloride
Pregnancy Category Note
Pregnancy category: C
Lactation: Unknown whether drug is excreted into breast milk; use caution
Interaction
Cyclopropane and halogenated hydrocarbon anaesthetics may sensitise myocardium to dopamine and precipitate ventricular arrhythmias. MAO inhibitors prolong and increase dopamine effects. Ergots potentiate vasoconstriction action of dopamine. Alpha-blockers unmask dopamine's beta action.