The digestive system quickly and completely absorbs methyldopa. It is widely dispersed throughout tissues, with the liver, kidney, heart, and lungs having the highest concentrations. The blood-brain barrier and placenta are both crossed by methyldopa. To produce alpha- and beta-methylnorepinephrine, it is metabolized in the liver. The urine is where these metabolites are eliminated. Methyldopa has a half-life of 8 to 12 hours in the body.
Modes of action
Methyldopa stimulates central alpha2 adrenergic receptors, which reduces sympathetic nerve outflow from the central nervous system. Heart rate, myocardial contractility, and peripheral vascular resistance all decrease as a result. After 2 weeks of therapy, the blood pressure gradually drops, and this usually happens. Methyldopa's antihypertensive effect is aided by its direct inhibitory effects on smooth muscle.
Hypertension can be treated with methyldopa. It can be used either on its own or in conjunction with other antihypertensive medications. Methyldopa is also useful for treating preeclampsia and gestational hypertension.
Dizziness, headaches, and fatigue are three of methyldopa's most frequent adverse effects. Usually, these side effects get better over time. Constipation, nausea, vomiting, dry mouth, and other side effects are also frequent. If these side effects do manifest, they typically get better over time. Additionally, this medication may make you sleepy. If you experience this side effect, avoid driving or operating heavy equipment. The liver enzymes may also rise as a result of this medication. Consult your doctor if you experience this side effect.
Methyldopa and other drugs may interact. Give your doctor a complete list of all the drugs and supplements you take. Elderly patients should use methyldopa with caution as they may be more sensitive to its side effects. The use of this medication in children is not advised.
Methyldopa may make you feel sleepy. If you experience this side effect, avoid driving or operating heavy equipment. The liver enzymes may also rise as a result of this medication. Consult your doctor if you experience this side effect. Pregnancy should not be treated with this medication unless the risks are outweighed by the potential benefits. Consult your doctor about the potential risks of taking this medication if you are pregnant or intend to become pregnant.
Inform your doctor if you have or have ever had kidney disease, pheochromocytoma (an adrenal gland tumor), or liver disease. Patients with diabetes mellitus should use methyldopa with caution because it has the potential to raise blood sugar levels. Methyldopa should be used cautiously in patients who have a history of depression because it has the potential to make things worse. This drug may make you feel sleepy. If you experience this side effect, avoid driving or operating heavy equipment.
Use of this medication during pregnancy is not advised. Consult your doctor about the potential risks of taking this medication if you are pregnant or intend to become pregnant. This drug is excreted in breast milk. It is not advised to breastfeed while using this medication. Before breastfeeding, speak with your doctor.
Methyldopa and other drugs may interact. Give your doctor a complete list of all the drugs and supplements you take. Only if the benefits of using this medication during pregnancy outweigh any possible risks to the fetus. Methyldopa has been linked to fetal toxicity, including bradycardia, hypotension, and lethargy in newborns, and it crosses the placenta. There are no sufficient and carefully monitored studies on methyldopa in expectant mothers. Only if the benefit outweighs the risk to the nursing infant should this medication be used while nursing. Methyldopa has been linked to sedation and irritability in nursing infants and is excreted in human milk. If you use methyldopa while breastfeeding, keep an eye out for these side effects in the baby.
Dosage and Administration
Aldomet comes in 250 mg and 500 mg tablet form. Two or three times a day, 250 mg, is the typical starting dose. Until the desired blood pressure lowering effect is realized or a maximum dose of 2000 mg per day is reached, the dose may be increased by 250 mg every 2-3 days.
The target dose range, given in two or three divided doses, is between 1000 and 3000 mg/day. A maintenance dosage should be set once the best response has been identified. 250–1000 mg/day, given in two or three divided doses, is the typical maintenance dosage range.
Patients who are elderly or who have hepatic impairment may require dosage adjustments. In patients with renal impairment, dosage adjustments are typically not required.
To lessen the likelihood of gastrointestinal side effects, Aldomet should be taken with food or milk.
Patients with diabetes mellitus, depression, or kidney disease should use aldomet with caution.
Hypotension, tachycardia, and drowsiness are signs of overdose. Supportive and symptomatic therapies are used. In the early stages of toxicity, gastric lavage and activated charcoal may be helpful. Intravenous labetalol or oral nifedipine may be used if hypertension still exists. Dialysis does not work.