Uses of Dopaflex: - Hypertension (high blood pressure) Hypertension Active liver disease (e.g. acute hepatitis, active cirrhosis) or depression. Concomitant use w/ MAOIs.

Centrally acting antihypertensive drugs (central sympatholytic)

Although the mechanism of action has yet to be conclusively demonstrated, the resultant hypotensive effect is most likely due to the drug's action on the CNS. Methyldopa is converted into the metabolite, alpha-methylnorepinephrine, in the CNS, where it stimulates the central inhibitory alpha-adrenergic receptors, leading to a reduction in sympathetic tone, total peripheral resistance, and blood pressure. Reduction in plasma renin activity, as well as the inhibition of both central and peripheral norepinephrine and serotonine production may also contribute to the drug's antihypertensive effect, although this is not a major mechanism of action. This is done through the inhibition of the decarboxylation of dihydroxyphenylalanine (dopa)- the precursor of norepinephrine, 5-hydroxytryptophan (5-HTP), serotonin (in the CNS) and in most peripheral tissues.

How to use Methyldopa: Take this medicine in the dose and duration as advised by your doctor. Swallow it as a whole. Do not chew, crush or break it. Methyldopa may be taken with or without food, but it is better to take it at a fixed time. Avoid Methyldopa with high protein meals such as cottage cheese, Swiss cheese, protein powder, eggs and milk. Administration: May be taken with or without food. Adult Dose: Oral Hypertension Adult: Monotherapy: Initially, 250 mg bid-tid for 2 days; adjust at intervals of at least 2 days according to response. Maintenance: 500-2,000 mg daily. Max: 3,000 mg daily. Combination therapy: Initial dose should not exceed 500 mg daily in divided doses. Elderly: Initially, 125 mg bid; gradually increase according to response. Max: 2,000 mg daily. Child Dose: Oral Hypertension Child: <12 yr Initially, 10 mg/kg or 300 mg/m2 daily in 2-4 divided doses; adjust at intervals of at least 2 days according to response. Max: 65 mg/kg, 2,000 mg/m2 or 3,000 mg daily, whichever is least. Renal Dose: Renal Impairment Adjust dosage frequency with renal impairment CrCl >50 mL/min: q8hr CrCl 10-50 mL/min: q8-12hr CrCl <10 mL/min: q12-24hr

Reduced hypotensive effects with phenothiazines, TCAs and possibly, amphetamines. Additive hypotensive effects with levodopa; psychosis may also occur. Reduced absorption and effects with oral iron preparations. Reduced doses of general anaesthetics may be required. Effect of ephedrine may be reduced. Potentially Fatal: Increased risk of severe hypertension with MAOIs. Increased lithium toxicity

Active liver disease (e.g. acute hepatitis, active cirrhosis) or depression. Concomitant use w/ MAOIs.

Common - Dizziness - Fatigue - Sleepiness - Dryness in mouth - Orthostatic hypotension (sudden lowering of blood pressure on standing) Drowsiness, orthostatic hypotension, nausea, headache, weakness, fatigue, decreased libido, impotence, impaired concentration and memory, mild psychoses, depression, disturbed sleep, nightmares, paraesthesias, Bell's palsy, parkinsonism, involuntary choreoathetotic movements, oedema, fluid retention, exacerbation of angina pectoris, bradycardia, syncope, prolonged carotid sinus hypersensitivity, paradoxical HTN, GI disturbances (e.g. nausea, vomiting, diarrhoea, constipation), black/sore tongue, inflamed salivary glands, dry mouth, fever, eosinophilia, liver function disturbances, hepatitis, lupus-like syndrome, rashes, lichenoid and granulomatous eruptions, toxic epidermal necrolysis, flu-like syndrome, nocturia, uraemia, nasal congestion, retroperitoneal fibrosis, hyperprolactinaemia, breast enlargement (including gynaecomastia), galactorrhoea, amenorrhoea. Rarely, pancreatitis and colitis, immune thrombocytopenia, reversible leucopenia (primarily granulocytopenia). Potentially Fatal: Hepatic necrosis, haemolytic anaemia, hypersensitivity myocarditis.

Pregnancy Category B. Methyldopa appears in breast milk. Therefore, caution should be exercised when Methyldopa is given to a nursing woman.

Precaution: Patient w/ history of haemolytic anaemia, liver disease or depression; parkinsonism, hepatic porphyria. Not intended for the treatment of phaeochromocytoma. Renal or hepatic impairment. Childn, elderly. Pregnancy and lactation. Patient Counselling May impair ability to drive or operate machinery. Monitoring Parameters Monitor BP, blood counts, liver enzymes; direct Coombs' test. Lactation: distributed in breast milk but not in clinically significant amounts; compatible w/ breastfeeding

Acute overdosage may produce acute hypotension with other responses attributable to brain and gastrointestinal malfunction (excessive sedation, weakness, bradycardia, dizziness, lightheadedness, constipation, distention, flatus, diarrhea, nausea, vomiting). In the event of overdosage, symptomatic and supportive measures should be employed. When ingestion is recent, gastric lavage or emesis may reduce absorption. When ingestion has been earlier, infusions may be helpful to promote urinary excretion.

Do not store above 30°C. Keep out of the reach of children.

Centrally acting antihypertensive drugs (central sympatholytic)

Methyldopa stimulates alpha 2-adrenoceptors which results in reduced sympathetic tone and fall in BP.

Pregnancy category B. Methyldopa appears in breast milk. Therefore, caution should be exercised when Methyldopa is given to a nursing woman.