Acute overdosage may produce acute hypotension with other responses attributable to brain and gastrointestinal malfunction (excessive sedation, weakness, bradycardia, dizziness, light-headedness, 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. Otherwise, management includes special attention to cardiac rate and output, blood volume, electrolyte balance, paralytic ileus, urinary function and cerebral activity.
Sympathomimetic drugs [e.g., levarterenol, epinephrine, metaraminol bitartrate] may be indicated.
Methyldopa is dialyzable.
The oral LD50 of methyldopa is greater than 1.5 g/kg in both the mouse and the rat.
The usual starting dosage of methyldopa tablet 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. By adjustment of dosage, morning hypotension may be prevented without sacrificing control of afternoon blood pressure.
When methyldopa is given to patients on other anti-hypertensives, the dose of these agents may need to be adjusted to effect a smooth transition. When methyldopa is given with anti-hypertensives other than thiazides, the initial dosage of methyldopa should be limited to 500 mg daily in divided doses; when methyldopa is added to a thiazide, the dosage of thiazide need not be changed.
The usual daily dosage of methyldopa 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 g. Once an effective dosage range is attained, a smooth blood pressure response occurs in most patients in 12 to 24 hours. Since methyldopa has a relatively short duration of action, withdrawal is followed by return of hypertension usually within 48 hours. This is not complicated by an overshoot of blood pressure.
Occasionally tolerance may occur, usually between the second and third month of therapy. Adding a diuretic or increasing the dosage of methyldopa frequently will restore effective control of blood pressure. A thiazide may be added at any time during methyldopa 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 g of methyldopa daily.
Methyldopa 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 (see PRECAUTIONS , Geriatric 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 g daily, whichever is less (see PRECAUTIONS , Pediatric Use).
Methyldopa Tablets USP are available as white to off-white, round, convex, unscored, film-coated tablets, debossed “N11” on one side, and plain on the other side, containing 250 mg of methyldopa USP, packaged in bottles of 90 tablets.
PHARMACIST: Dispense in a well-closed container as defined in the USP, with a child-resistant closure (as required).
Store at 20° to 25° C (68° to 77° F) [See USP Controlled Room Temperature].
Manufactured In India By:
EMCURE PHARMACEUTICALS LTD.
Hinjwadi, Pune, India
TEVA PHARMACEUTICALS USA
Sellersville, PA 18960
REBEL DISTRIBUTORS CORP.
Thousand Oaks, CA 91320
| METHYLDOPA |
methyldopa tablet, film coated
|Labeler — Rebel Distributors Corp (118802834)|
|Registrant — PSS World Medical, Inc. (101822862)|
|PSS World Medical, Inc.||791528623||REPACK (42254-351)|
|STAT RX USA LLC||786036330||REPACK (42254-351)|
|Dispensing Solutions, Inc.||066070785||RELABEL (42254-351), REPACK (42254-351)|
|SCRIPT PAK||964420108||RELABEL (42254-351), REPACK (42254-351)|
|Keltman Pharmaceuticals, Inc.||362861077||REPACK (42254-351)|
|Rebel Distirbutors Corp.||118802834||RELABEL (42254-351), REPACK (42254-351)|
Revised: 12/2012 Rebel Distributors Corp
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