Drug Interactions between fosphenytoin and mephobarbital
This report displays the potential drug interactions for the following 2 drugs:
- fosphenytoin
- mephobarbital
Interactions between your drugs
mephobarbital fosphenytoin
Applies to: mephobarbital and fosphenytoin
MONITOR: Barbiturates may induce or inhibit the metabolism of phenytoin. Plasma phenytoin concentrations may be decreased or increased. The mechanism are induction of hepatic CYP450 phenytoin metabolism by therapeutic doses of barbiturates, and competitive inhibition of metabolism by large doses. Also, when phenytoin is added to a regimen, the plasma levels of barbiturates may significantly increase via an unknown mechanism.
MANAGEMENT: Close laboratory and clinical observation for altered effects of both agents is recommended when doses of either agent are started, changed, or discontinued. Patients should be advised to notify their physician if they experience loss of seizure control or excessive or prolonged sedative effects. It may be necessary to alter the dosage of one or both of the drugs.
References (2)
- Yoshida N, Oda Y, Nishi S, Abe J, Kaji A, Asada A, Fujimori M (1993) "Effect of barbiturate therapy on phenytoin pharmacokinetics." Crit Care Med, 21, p. 1514-22
- Kuranari M, Tatsukawa H, Seike M, et al. (1995) "Effect of phenytoin on phenobarbital pharmacokinetics in a patient with epilepsy." Ann Pharmacother, 29, p. 83-4
Drug and food interactions
mephobarbital food
Applies to: mephobarbital
GENERALLY AVOID: Concurrent acute use of barbiturates and ethanol may result in additive CNS effects, including impaired coordination, sedation, and death. Tolerance of these agents may occur with chronic use. The mechanism is related to inhibition of microsomal enzymes acutely and induction of hepatic microsomal enzymes chronically.
MANAGEMENT: The combination of ethanol and barbiturates should be avoided.
References (5)
- Gupta RC, Kofoed J (1966) "Toxological statistics for barbiturates, other sedatives, and tranquilizers in Ontario: a 10-year survey." Can Med Assoc J, 94, p. 863-5
- Misra PS, Lefevre A, Ishii H, Rubin E, Lieber CS (1971) "Increase of ethanol, meprobamate and pentobarbital metabolism after chronic ethanol administration in man and in rats." Am J Med, 51, p. 346-51
- Saario I, Linnoila M (1976) "Effect of subacute treatment with hypnotics, alone or in combination with alcohol, on psychomotor skills related to driving." Acta Pharmacol Toxicol (Copenh), 38, p. 382-92
- Stead AH, Moffat AC (1983) "Quantification of the interaction between barbiturates and alcohol and interpretation of fatal blood concentrations." Hum Toxicol, 2, p. 5-14
- Seixas FA (1979) "Drug/alcohol interactions: avert potential dangers." Geriatrics, 34, p. 89-102
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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