Generic Name: Dilantin
What is Dilantin?
If coadministration is necessary, monitor for changes in the efficacy of cabazitaxel. Cabozantinib: Avoid concomitant use of cabozantinib with phenytoin due to the risk of decreased cabozantinib efficacy. If the use of both agents is necessary, increase the daily cabozantinib capsules Cometriq dose as tolerated by 40 mg e.
Resume the prior cabozantinib dose after 2 to 3 days if phenytoin is discontinued. Cabozantinib is primarily metabolized by CYP3A4 and phenytoin is a strong CYP3A4 inducer.
Caffeine: The metabolism of caffeine, can be increased by concurrent use with medications that cause induction of hepatic CYP450 enzymes like the hydantoin anticonvulsants. Calcifediol: Dose adjustment of calcifediol may be necessary during coadministration with phenytoin. Additionally, serum 25-hydroxyvitamin D, intact PTH, and calcium concentrations should be closely monitored if a patient initiates or discontinues therapy with phenytoin.
Phenytoin stimulates microsomal hydroxylation and reduces the half-life of calcifediol. Calcitriol: Anticonvulsants, such phenytoin and fosphenytoin which is metabolized to phenytoincan increase the metabolism of endogenous vitamin D, thereby lowering serum concentrations and decreasing its activity.
Dosage adjustments of vitamin D analogs may be required in patients who are receiving chronic treatment with anticonvulsants.
Ulipristal: Ulipristal is a substrate of CYP3A4 and phenytoin is a CYP3A4 inducer. Concomitant use may decrease the plasma concentration and effectiveness of ulipristal. Valacyclovir: The addition of valacyclovir to phenytoin may lead to a clinically significant decrease in phenytoin serum concentrations and loss of seizure control. Clinicians should be prepared to make adjustments in phenytoin dosing if valacyclovir therapy is added or discontinued.
Valbenazine: Co-administration of strong CYP3A4 inducers, such as Phenytoin, and valbenazine, a CYP3A4 substrate, is not recommended. Strong CYP3A4 inducers can decrease systemic exposure of valbenazine and its active metabolite compared to the use of valbenazine alone. Reduced exposure of valbenazine and its active metabolite may reduce efficacy.
Valdecoxib: Phenytoin acts as an inducer of cytochrome P450 enzymes. Patients stabilized on valdecoxib therapy should be closely monitored for loss of pain symptom control when phenytoin therapy is added. Valproic Acid, Divalproex Sodium: Phenytoin and valproic acid should be used together with caution. Valproic acid can displace phenytoin from protein-binding sites and inhibit its metabolism.
How should I take Dilantin?
In addition, indinavir may inhibit the CYP metabolism of hydantoins, resulting in increased hydantoin concentrations. Influenza Virus Vaccine: Although influenza virus vaccine has been reported to inhibit the clearance of medications metabolized by cytochrome P-450 including phenytoin, the reports concerning possible toxicity are conflicting. The use of these medications should not prohibit influenza immunization if indicated. Insulins: Phenytoin and other hydantoins have the potential to increase blood glucose and thus interact with antidiabetic agents pharmacodynamically.
Intranasal Influenza Vaccine: Although influenza virus vaccine has been reported to inhibit the clearance of medications metabolized by cytochrome P-450 including phenytoin, the reports concerning possible toxicity are conflicting.
What should I avoid while taking Dilantin?
Also, theophylline may inhibit the oral absorption of phenytoin. Thiazolidinediones: Phenytoin and other hydantoins have the potential to increase blood glucose and thus interact with antidiabetic agents pharmacodynamically.
Thiopental: Barbiturates can stimulate the hydroxylating enzyme that metabolizes phenytoin or, conversely, may inhibit phenytoin or fosphenytoin metabolism. Thiothixene: Thiothixene, when used concomitantly with various anticonvulsants can increase CNS depression and also can lower the seizure threshold.
Thyroid hormones: Hydantoin anticonvulsants induce hepatic microsomal enzymes and may increase the metabolism of thyroid hormones, leading to reduced efficacy of the thyroid hormone. Tiagabine had no effect on the steady-state plasma concentrations of phenytoin when evaluated in patients with epilepsy. Tiagabine does not appear to be an inducer or inhibitor of the hepatic microsomal enzyme system.
Use of tiagabine WITHOUT enzyme-inducing antiepileptic drugs results in blood levels about two times those attained in the studies on which dosing recommendations for partial seizures are based.
Dilantin side effects
A higher hydrocodone dose may be needed if used with fosphenytoin. Phenytoin or fosphenytoin, an inducer of CYP3A4, may cause increased clearance of oxycodone, which could result in lack of efficacy or the development of an abstinence syndrome in a patient who had developed physical dependence to oxycodone.
If coadministration of these agents is necessary, monitor patients at frequent intervals and consider dose adjustments if needed. The analgesic activity of propoxyphene may be reduced.
Hydantoins may also cause additive CNS depression with propoxyphene. The use of tramadol in patients on anticonvulsant medications for seizure therapy is not recommended. In addition, the hepatic metabolism of tramadol may be accelerated by the use of ethotoin, phenytoin, or fosphenytoin.
Acitretin: Acitretin reduces the protein binding of phenytoin.
Common Dilantin ide effects may include:
Your doctor will need to check your progress at regular visits while you are using Dilantin.
While the clinical relevance of this interaction is uncertain, concurrent use should be undertaken with care.
Do I need a prescription for Dilantin.
I have used it for 13 years with no side effects and have no seizures : Just my two cents.
In addition, because imatinib inhibits CYP2C9, the metabolism of phenytoin may be decreased by imatinib. Close monitoring of anticonvulsant serum concentrations is warranted due to the potential complex interactions that may take place with concurrent imatinib therapy.
Imipramine: Tricyclic antidepressants TCAwhen used concomitantly with anticonvulsants, can increase CNS depression and may also lower the seizure threshold, leading to pharmacodynamic interactions.
Where can I get more information?
An increased dose of eslicarbazepine may be necessary if these drugs are coadministered.
A strong CYP3A inducer can decrease the efficacy of netupitant by substantially reducing plasma concentrations of netupitant.