Dopamet250 mg

Dopamet 250 mg is indicated in Hypertension.

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. Dopamet 250 mg 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.

Adult Use- Initiation of Therapy: The usual starting dosage of Dopamet 250 mg is 250 mg two or three times a day in the first 48 hours. The daily dosage then may be increased or decreased, preferably at intervals of not less than two days, until an adequate response is achieved. To minimize the sedation, start dosage increases in the evening. When Dopamet 250 mg is given to patients on other antihypertensives, the dose of these agents may need to be adjusted to effect a smooth transition. When Dopamet 250 mg is given with antihypertensives other than thiazides, the initial dosage of Dopamet 250 mg should be limited to 500 mg daily in divided doses; when Dopamet 250 mg is added to a thiazide, the dosage of thiazide need not to be changed. Maintenance Therapy: The usual daily dosage of Dopamet 250 mg is 500 mg to 2 g in two to four doses. Although occasional patients have responded to higher doses, the maximum recommended daily dosage is 3 gm. Occasionally tolerance may occur, usually between the second and third month of therapy. Adding a diuretic or increasing the dosage of Dopamet 250 mg frequently will restore effective control of blood pressure. A thiazide may be added at any time during Dopamet 250 mg therapy and is recommended if therapy has not been started with a thiazide or if effective control of blood pressure cannot be maintained on 2 gm of Dopamet 250 mg daily. Dopamet 250 mg is largely excreted by the kidney and patients with impaired renal function may respond to smaller doses. Syncope in older patients may be related to an increased sensitivity and advanced arteriosclerotic vascular disease. This may be avoided by lower doses.  Pediatric Use- Initial dosage is based on 10 mg/kg of body weight daily in two to four doses. The daily dosage then is increased or decreased until an adequate response is achieved. The maximum dosage is 65 mg/kg or 3 gm daily, whichever is less.

Adults- Initiation of Therapy: The usual starting dosage of Dopamet 250 mg is 250 mg two or three times a day in the first 48 hours. The daily dosage then may be increased or decreased, preferably at intervals of not less than two days, until an adequate response is achieved. To minimize the sedation, start dosage increases in the evening. When Dopamet 250 mg is given to patients on other antihypertensives, the dose of these agents may need to be adjusted to effect a smooth transition. When Dopamet 250 mg is given with antihypertensives other than thiazides, the initial dosage of Dopamet 250 mg should be limited to 500 mg daily in divided doses; when Dopamet 250 mg is added to a thiazide, the dosage of thiazide need not to be changed. Maintenance Therapy: The usual daily dosage of Dopamet 250 mg is 500 mg to 2 g in two to four doses. Although occasional patients have responded to higher doses, the maximum recommended daily dosage is 3 gm. Occasionally tolerance may occur, usually between the second and third month of therapy. Adding a diuretic or increasing the dosage of Dopamet 250 mg frequently will restore effective control of blood pressure. A thiazide may be added at any time during Dopamet 250 mg therapy and is recommended if therapy'has not been started with a thiazide or if effective control of blood pressure cannot be maintained on 2 gm of Dopamet 250 mg daily. Dopamet 250 mg is largely excreted by the kidney and patients with impaired renal function may respond to smaller doses. Syncope in older patients may be related to an increased sensitivity and advanced arteriosclerotic vascular disease. This may be avoided by lower doses. Pediatric Use: Initial dosage is based on 10 mg/kg of body weight daily in two to four doses. The daily dosage then is increased or decreased until an adequate response is achieved. The maximum dosage is 65 mg/kg or 3 gm daily, whichever is less.

When Dopamet 250 mg is used with other antihypertensive drugs, potentiation of antihypertensive effect may occur. Patients may require reduced doses of anesthetics when on Dopamet 250 mg. When Dopamet 250 mg and lithium are given concomitantly the patient should be carefully monitored for symptoms of lithium toxicity. Coadministration of Dopamet 250 mg with ferrous sulfate or ferrous gluconate is not recommended.

Dopamet 250 mg is contraindicated in patients: with active hepatic disease, such as acute hepatitis and active cirrhosis with liver disorders previously associated with Dopamet 250 mg therapy with hypersensitivity to any component of these products on therapy with monoamine oxidase (MAO) inhibitors.

Sedation, usually transient, may occur during the initial period of therapy or whenever the dose is increased. Headache, asthenia, or weakness may be noted as early and transient symptoms. The following systemic side effects may rarely occur with the use of Dopamet 250 mg- angina pectoris, congestive heart failure, orthostatic hypotension, edema or weight gain, bradycardia, pancreatitis, colitis, vomiting, diarrhea, nausea, constipation, dryness of mouth, hyperprolactinemia, bone marrow depression, leukopenia, granulocytopenia, thrombocytopenia, hemolytic anemia; rheumatoid factor, hepatitis, jaundice, myocarditis, pericarditis, vasculitis, eosinophilia, parkinsonism, bell's palsy, nightmares and reversible mild psychoses or depression, dizziness, lightheadedness, paresthesias, arthralgia, myalgia, nasal stuffiness, rash, amenorrhea, gynecomastia, lactation, impotence. However, significant adverse effects due to Dopamet 250 mg have been infrequent and this agent usually is well tolerated.

Pregnancy Category B. Dopamet 250 mg appears in breast milk. Therefore, caution should be exercised when Dopamet 250 mg is given to a nursing woman.

Dopamet 250 mg should be used with caution in patients with a history of previous liver disease or dysfunction. Some patients taking Dopamet 250 mg experience clinical edema or weight gain, which may be controlled by use of a diuretic. Dopamet 250 mg should not be continued if edema progresses or signs of heart failure appear. Hypertension has recurred occasionally after dialysis in patients given Dopamet 250 mg because the drug is removed by this procedure. Rarely involuntary choreoathetotic movements have been observed during therapy with Dopamet 250 mg in patients with severe bilateral cerebrovascular disease. If these movements occur, stop therapy

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.

Pediatric Use: There are no well-controlled clinical trials in pediatric patients. Information on dosing in pediatric patients is supported by evidence from published literature regarding the treatment of hypertension in pediatric patients.

Centrally acting antihypertensive drugs (central sympatholytic)

Dopamet 250 mg, or α-Dopamet 250 mg, is a centrally acting sympatholytic agent and an antihypertensive agent. It is an analog of DOPA (3,4‐hydroxyphenylanine), and it is a prodrug, meaning that the drug requires biotransformation to an active metabolite for therapeutic effects. Dopamet 250 mg works by binding to alpha(α)-2 adrenergic receptors as an agonist, leading to the inhibition of adrenergic neuronal outflow and reduction of vasoconstrictor adrenergic signals. Dopamet 250 mg exists in two isomers D-α-Dopamet 250 mg and L-α-Dopamet 250 mg, which is the active form.First introduced in 1960 as an antihypertensive agent, Dopamet 250 mg was considered to be useful in certain patient populations, such as pregnant women and patients with renal insufficiency. Since then, Dopamet 250 mg was largely replaced by newer, better-tolerated antihypertensive agents; however, it is still used as monotherapy or in combination with hydrochlorothiazide. Dopamet 250 mg is also available as intravenous injection, which is used to manage hypertension when oral therapy is unfeasible and to treat hypertensive crisis.

Pregnancy category B. Dopamet 250 mg appears in breast milk. Therefore, caution should be exercised when Dopamet 250 mg is given to a nursing woman.

Pediatric Use: There are no well-controlled clinical trials in pediatric patients. Information on dosing in pediatric patients is supported by evidence from published literature regarding the treatment of hypertension in pediatric patients.