Drug Interactions between methyldopa and Mintuss NX

GENERALLY AVOID: Alcohol may potentiate the central nervous system (CNS) depressant effects of opioid analgesics including hydrocodone. Concomitant use may result in additive CNS depression and impairment of judgment, thinking, and psychomotor skills. In more severe cases, hypotension, respiratory depression, profound sedation, coma, or even death may occur.

GENERALLY AVOID: Consumption of alcohol while taking some sustained-release formulations of hydrocodone may cause rapid release of the drug, resulting in high systemic levels of hydrocodone that may be potentially lethal. Alcohol apparently can disrupt the release mechanism of some sustained-release formulations. In study subjects, the rate of absorption of hydrocodone from an extended-release formulation was found to be affected by coadministration with 40% alcohol in the fasted state, as demonstrated by an average 2.4-fold (up to 3.9-fold in one subject) increase in hydrocodone peak plasma concentration and a decrease in the time to peak concentration. Alcohol also increased the extent of absorption by an average of 1.2-fold (up to 1.7-fold in one subject).

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of hydrocodone. The proposed mechanism is inhibition of CYP450 3A4-mediated metabolism of hydrocodone by certain compounds present in grapefruit. Increased hydrocodone concentrations could conceivably increase or prolong adverse drug effects and may cause potentially fatal respiratory depression.

MANAGEMENT: Patients taking sustained-release formulations of hydrocodone should not consume alcohol or use medications that contain alcohol. In general, potent narcotics such as hydrocodone should not be combined with alcohol. Patients should also avoid consumption of grapefruit or grapefruit juice during treatment with hydrocodone.

Switch to consumer interaction data

MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.

MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.

Switch to consumer interaction data

ADJUST DOSING INTERVAL: The oral bioavailability and pharmacologic effects of methyldopa may be decreased during concurrent administration with iron-containing products. The proposed mechanism is chelation of methyldopa by the iron cation, forming an insoluble complex that is poorly absorbed from the gastrointestinal tract. In one study, five hypertensive patients receiving chronic methyldopa therapy (250 mg to 1500 mg daily) all had elevated blood pressure following the addition of ferrous sulfate 325 mg three times daily for 2 weeks. The systolic pressure had increased by more than 15 mmHg in three of the patients and the diastolic pressure increased by more than 10 mmHg in two. Blood pressure returned to baseline within 7 days of discontinuing the iron. In 12 normal subjects, administration of methyldopa 500 mg with ferrous sulfate 325 mg or ferrous gluconate 600 mg resulted in an 88% and 79% reduction, respectively, in the renal excretion of unmetabolized, free methyldopa compared to administration of methyldopa alone. In another study, administration of ferrous sulfate simultaneously with methyldopa reduced the bioavailability of methyldopa by 83%, while administration one hour or two hours before methyldopa reduced its bioavailability by 55% and 42%, respectively.

MANAGEMENT: Until more information is available, patients receiving methyldopa in combination with iron-containing products should be advised to separate the times of administration by as much as possible. Patients should be monitored closely for altered hypertensive effect and methyldopa dosage increased as necessary. Selection of an alternative antihypertensive therapy may be necessary.

Switch to consumer interaction data