Dosing & Uses
Tonic Clonic & Complex Partial Seizures
Initial: Up to 1 g/d PO in 4-6 divided doses;
Maint: 2-3 g/d
Administration
Take after food
Other Information
Monitor: CBC, LFTs
Other Indications & Uses
Tonic clonic (grand mal) & complex partial seizures
Tonic Clonic & Complex Partial Seizures
Initial: Up to 750 mg/d PO in 4-6 divided doses;
Maint: Usual 500 mg-1 g/d PO; rarely 2 g/d or more
Administration
Take after food
Other Information
Monitor: CBC, LFTs
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (1)
- dofetilide
ethotoin, dofetilide. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Additive cardiac effects.
Serious - Use Alternative (9)
- cyclosporine
ethotoin decreases levels of cyclosporine by increasing metabolism. Avoid or Use Alternate Drug.
- dopamine
ethotoin, dopamine. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased risk of hypotension.
- efavirenz
efavirenz will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug.
- mebendazole
ethotoin decreases levels of mebendazole by increasing metabolism. Contraindicated.
- mestranol
ethotoin decreases levels of mestranol by increasing metabolism. Avoid or Use Alternate Drug. May result in contraceptive failure.
- methadone
ethotoin decreases levels of methadone by increasing metabolism. Contraindicated.
- metoclopramide intranasal
ethotoin, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.
- olopatadine intranasal
ethotoin and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.
- ropeginterferon alfa 2b
ropeginterferon alfa 2b and ethotoin both increase Other (see comment). Avoid or Use Alternate Drug. Narcotics, hypnotics or sedatives can produce additive neuropsychiatric side effects. Avoid use and monitor patients receiving the combination for effects of excessive CNS toxicity.
Monitor Closely (104)
- acrivastine
acrivastine and ethotoin both increase sedation. Use Caution/Monitor.
- amiodarone
amiodarone will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- amisulpride
amisulpride and ethotoin both increase sedation. Use Caution/Monitor.
- amobarbital
amobarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- antithrombin alfa
antithrombin alfa increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, antithrombin alfa. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - antithrombin III
antithrombin III increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, antithrombin III. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - argatroban
argatroban increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, argatroban. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - asenapine
asenapine and ethotoin both increase sedation. Use Caution/Monitor.
- asenapine transdermal
asenapine transdermal and ethotoin both increase sedation. Use Caution/Monitor.
- avapritinib
avapritinib and ethotoin both increase sedation. Use Caution/Monitor.
- bemiparin
bemiparin increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, bemiparin. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - benzhydrocodone/acetaminophen
benzhydrocodone/acetaminophen and ethotoin both increase sedation. Use Caution/Monitor.
- bivalirudin
bivalirudin increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, bivalirudin. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - bleomycin
bleomycin decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor.
- bosentan
bosentan will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- brexanolone
brexanolone, ethotoin. Either increases toxicity of the other by sedation. Use Caution/Monitor.
- brexpiprazole
brexpiprazole and ethotoin both increase sedation. Use Caution/Monitor.
- brimonidine
brimonidine and ethotoin both increase sedation. Use Caution/Monitor.
- brivaracetam
brivaracetam and ethotoin both increase sedation. Use Caution/Monitor.
- buprenorphine subdermal implant
buprenorphine subdermal implant and ethotoin both increase sedation. Use Caution/Monitor.
- buprenorphine transdermal
buprenorphine transdermal and ethotoin both increase sedation. Use Caution/Monitor.
- buprenorphine, long-acting injection
buprenorphine, long-acting injection and ethotoin both increase sedation. Use Caution/Monitor.
- busulfan
ethotoin decreases levels of busulfan by increasing hepatic clearance. Use Caution/Monitor.
- butabarbital
butabarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- butalbital
butalbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- capecitabine
capecitabine increases levels of ethotoin by unknown mechanism. Use Caution/Monitor. Based on case reports.
- carbamazepine
carbamazepine will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- carboplatin
carboplatin decreases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
- carmustine
carmustine decreases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
- cenobamate
cenobamate, ethotoin. Either increases effects of the other by sedation. Use Caution/Monitor.
- cimetidine
cimetidine will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- cisplatin
cisplatin decreases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
- dabigatran
dabigatran increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, dabigatran. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - dalteparin
dalteparin increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, dalteparin. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - daridorexant
ethotoin and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.
- decitabine
decitabine increases levels of ethotoin by unknown mechanism. Use Caution/Monitor. Based on case reports.
- deutetrabenazine
ethotoin and deutetrabenazine both increase sedation. Use Caution/Monitor.
- difelikefalin
difelikefalin and ethotoin both increase sedation. Use Caution/Monitor.
- disopyramide
ethotoin increases toxicity of disopyramide by increasing metabolism. Use Caution/Monitor. Hydantoins decreases the level, but increases the toxicity, of disopyramide.
- disulfiram
disulfiram will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- docetaxel
docetaxel decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
docetaxel decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - doxorubicin
doxorubicin decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor.
- doxorubicin liposomal
doxorubicin liposomal decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor.
- enoxaparin
enoxaparin increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, enoxaparin. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - esketamine intranasal
esketamine intranasal, ethotoin. Either increases toxicity of the other by sedation. Use Caution/Monitor.
- eslicarbazepine acetate
ethotoin decreases levels of eslicarbazepine acetate by increasing metabolism. Modify Therapy/Monitor Closely.
- etravirine
etravirine will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- felbamate
felbamate will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- felodipine
ethotoin decreases levels of felodipine by increasing metabolism. Use Caution/Monitor.
- fleroxacin
fleroxacin decreases effects of ethotoin by unknown mechanism. Use Caution/Monitor. There are also case reports of quinolones increasing phenytoin levels.
- floxuridine
floxuridine increases levels of ethotoin by unknown mechanism. Use Caution/Monitor. Based on case reports.
- fluconazole
fluconazole will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- fluorouracil
fluorouracil increases levels of ethotoin by unknown mechanism. Use Caution/Monitor. Based on case reports.
- fluoxetine
fluoxetine will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- fluvoxamine
fluvoxamine will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- fondaparinux
fondaparinux increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, fondaparinux. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - ganaxolone
ethotoin and ganaxolone both increase sedation. Use Caution/Monitor.
- gemifloxacin
gemifloxacin decreases effects of ethotoin by unknown mechanism. Use Caution/Monitor. There are also case reports of quinolones increasing phenytoin levels.
- heparin
heparin increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, heparin. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - imatinib
imatinib will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- ketoconazole
ketoconazole will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- lamotrigine
ethotoin decreases levels of lamotrigine by increasing metabolism. Use Caution/Monitor.
- leflunomide
leflunomide will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- lemborexant
ethotoin, lemborexant. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.
- levofloxacin
levofloxacin decreases effects of ethotoin by unknown mechanism. Use Caution/Monitor. There are also case reports of quinolones increasing phenytoin levels.
- levoketoconazole
levoketoconazole will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- lurasidone
lurasidone, ethotoin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.
- mavacamten
ethotoin will increase the level or effect of mavacamten by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Inititiation of weak CYP2C19 inhibitors may require decreased mavacamten dose.
- mestranol
mestranol decreases effects of ethotoin by decreasing metabolism. Use Caution/Monitor.
- methylphenidate transdermal
methylphenidate transdermal will increase the level or effect of ethotoin by decreasing metabolism. Modify Therapy/Monitor Closely. Consider decreasing the dose of these drugs when given coadministered with methylphenidate. Monitor for drug toxiticities when initiating or discontinuing methylphenidate.
- metronidazole
metronidazole will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- metyrapone
ethotoin decreases levels of metyrapone by increasing metabolism. Use Caution/Monitor.
- mexiletine
ethotoin decreases levels of mexiletine by increasing metabolism. Use Caution/Monitor.
- miconazole vaginal
miconazole vaginal will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- midazolam intranasal
midazolam intranasal, ethotoin. Either increases levels of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.
- mitoxantrone
mitoxantrone decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor.
- moxifloxacin
moxifloxacin decreases effects of ethotoin by unknown mechanism. Use Caution/Monitor. There are also case reports of quinolones increasing phenytoin levels.
- nateglinide
nateglinide will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- ofloxacin
ofloxacin decreases effects of ethotoin by unknown mechanism. Use Caution/Monitor. There are also case reports of quinolones increasing phenytoin levels.
- orlistat
orlistat decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Risk of convulsions.
- paclitaxel
paclitaxel decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
paclitaxel decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - paclitaxel protein bound
paclitaxel protein bound decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
paclitaxel protein bound decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - pentobarbital
pentobarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- phenindione
phenindione increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, phenindione. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - phenobarbital
phenobarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- posaconazole
ethotoin decreases levels of posaconazole by increasing metabolism. Use Caution/Monitor.
- primidone
primidone will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
ethotoin increases effects of primidone by increasing metabolism. Use Caution/Monitor. Phenytoin enhances the conversion of primidone to phenobarbital. - protamine
protamine increases levels of ethotoin by unknown mechanism. Use Caution/Monitor.
ethotoin, protamine. Other (see comment). Use Caution/Monitor. Comment: Hydantoin anticonvulsants increase anticoagulant effects at first, then decrease those effects with continued use (2+ wks). There are multiple mechanisms involved, including enzyme induction, plasma protein binding site competition, and additive effects on prothrombin time. - quinidine
ethotoin decreases levels of quinidine by increasing metabolism. Use Caution/Monitor.
- rifampin
rifampin will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- rifapentine
rifapentine will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- secobarbital
secobarbital will decrease the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- sorafenib
ethotoin decreases levels of sorafenib by increasing metabolism. Use Caution/Monitor.
- sulfamethoxazole
sulfamethoxazole will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- ticlopidine
ticlopidine will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- treosulfan
treosulfan decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
treosulfan decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - valproic acid
valproic acid will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- vinblastine
vinblastine decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
vinblastine decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - vincristine
vincristine decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
vincristine decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - vincristine liposomal
vincristine liposomal decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
vincristine liposomal decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - vindesine
vindesine decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
vindesine decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - vinorelbine
vinorelbine decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.
vinorelbine decreases levels of ethotoin by increasing metabolism. Use Caution/Monitor. - voriconazole
voriconazole will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
- zafirlukast
zafirlukast will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
Minor (53)
- acetazolamide
acetazolamide, ethotoin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.
- auranofin
auranofin increases levels of ethotoin by unspecified interaction mechanism. Minor/Significance Unknown.
- brinzolamide
brinzolamide, ethotoin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.
- carbamazepine
carbamazepine, ethotoin. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Carbamazepine may increase or decrease phenytoin levels.
- caspofungin
ethotoin decreases levels of caspofungin by increasing metabolism. Minor/Significance Unknown.
- chloramphenicol
chloramphenicol increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- clopidogrel
clopidogrel increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- diazoxide
diazoxide decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown.
- disulfiram
disulfiram increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- doxycycline
ethotoin decreases levels of doxycycline by increasing metabolism. Minor/Significance Unknown.
- ethanol
ethanol decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown.
- ethosuximide
ethosuximide increases effects of ethotoin by pharmacodynamic synergism. Minor/Significance Unknown.
- felbamate
ethotoin decreases levels of felbamate by increasing metabolism. Minor/Significance Unknown. Toxicity increased with combination.
- folic acid
folic acid decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown. Large doses of folic acid (>10 mg/day).
- furosemide
ethotoin decreases levels of furosemide by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- immune globulin IM (IGIM)
ethotoin, immune globulin IM (IGIM). Mechanism: unknown. Minor/Significance Unknown. Risk of hypersensitivity myocarditis.
- immune globulin IV (IGIV)
ethotoin, immune globulin IV (IGIV). Mechanism: unknown. Minor/Significance Unknown. Risk of hypersensitivity myocarditis.
- immune globulin SC
ethotoin, immune globulin SC. Mechanism: unknown. Minor/Significance Unknown. Risk of hypersensitivity myocarditis (theoretical interaction, based on IM and IV immune globulin).
- influenza virus vaccine quadrivalent
influenza virus vaccine quadrivalent, ethotoin. Mechanism: unknown. Minor/Significance Unknown. Vaccine administration may incr or decr phenytoin levels.
- influenza virus vaccine quadrivalent, cell-cultured
influenza virus vaccine quadrivalent, cell-cultured, ethotoin. Mechanism: unknown. Minor/Significance Unknown. Vaccine administration may incr or decr phenytoin levels.
- influenza virus vaccine trivalent
influenza virus vaccine trivalent, ethotoin. Mechanism: unknown. Minor/Significance Unknown. Vaccine administration may incr or decr phenytoin levels.
- influenza virus vaccine trivalent, recombinant
influenza virus vaccine trivalent, recombinant, ethotoin. Mechanism: unknown. Minor/Significance Unknown. Vaccine administration may incr or decr phenytoin levels.
- isoniazid
isoniazid increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- L-methylfolate
L-methylfolate decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown.
- levoketoconazole
ethotoin will decrease the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
- levothyroxine
ethotoin decreases levels of levothyroxine by increasing metabolism. Minor/Significance Unknown.
ethotoin decreases levels of levothyroxine by plasma protein binding competition. Minor/Significance Unknown. - liothyronine
ethotoin decreases levels of liothyronine by increasing metabolism. Minor/Significance Unknown.
ethotoin decreases levels of liothyronine by plasma protein binding competition. Minor/Significance Unknown. - lithium
ethotoin increases toxicity of lithium by unknown mechanism. Minor/Significance Unknown.
- meperidine
ethotoin decreases levels of meperidine by increasing metabolism. Minor/Significance Unknown.
- methazolamide
methazolamide, ethotoin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of anticonvulsant induced osteomalacia.
- methsuximide
methsuximide increases effects of ethotoin by pharmacodynamic synergism. Minor/Significance Unknown.
- oxcarbazepine
ethotoin decreases levels of oxcarbazepine by increasing metabolism. Minor/Significance Unknown.
- phenobarbital
phenobarbital decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown. Phenobarbital may occasionally not change or even increase (via competitive inhibition) phenytoin levels.
- pyridoxine
pyridoxine decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown. High dose of pyridoxine (vitamin B6), >=200 mg/day.
- pyridoxine (Antidote)
pyridoxine (Antidote) decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown. High dose of pyridoxine (vitamin B6), >=200 mg/day.
- pyrimethamine
pyrimethamine decreases effects of ethotoin by pharmacodynamic antagonism. Minor/Significance Unknown.
- rifabutin
rifabutin decreases levels of ethotoin by increasing metabolism. Minor/Significance Unknown.
- sucralfate
sucralfate decreases levels of ethotoin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- sulfadiazine
sulfadiazine increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- sulfamethoxazole
sulfamethoxazole increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- sulfisoxazole
sulfisoxazole increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
- thyroid desiccated
ethotoin decreases levels of thyroid desiccated by increasing metabolism. Minor/Significance Unknown.
ethotoin decreases levels of thyroid desiccated by plasma protein binding competition. Minor/Significance Unknown. - tiagabine
ethotoin decreases levels of tiagabine by increasing metabolism. Minor/Significance Unknown.
- tibolone
ethotoin decreases levels of tibolone by increasing metabolism. Minor/Significance Unknown. Theoretical interaction.
- tolazamide
tolazamide increases levels of ethotoin by plasma protein binding competition. Minor/Significance Unknown.
- tolbutamide
tolbutamide increases levels of ethotoin by plasma protein binding competition. Minor/Significance Unknown.
ethotoin decreases effects of tolbutamide by pharmacodynamic antagonism. Minor/Significance Unknown. - topiramate
topiramate increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
ethotoin decreases levels of topiramate by increasing metabolism. Minor/Significance Unknown. - trazodone
trazodone increases levels of ethotoin by unspecified interaction mechanism. Minor/Significance Unknown.
- typhoid polysaccharide vaccine
ethotoin decreases levels of typhoid polysaccharide vaccine by increasing metabolism. Minor/Significance Unknown.
- typhoid vaccine live
ethotoin decreases levels of typhoid vaccine live by increasing metabolism. Minor/Significance Unknown.
- valproic acid
valproic acid, ethotoin. Mechanism: plasma protein binding competition. Minor/Significance Unknown. Valproic acid may increase or decrease phenytoin levels.
ethotoin decreases levels of valproic acid by increasing metabolism. Minor/Significance Unknown. - vigabatrin
vigabatrin decreases levels of ethotoin by unknown mechanism. Minor/Significance Unknown.
- voriconazole
voriconazole increases levels of ethotoin by decreasing metabolism. Minor/Significance Unknown.
ethotoin decreases levels of voriconazole by increasing metabolism. Minor/Significance Unknown.
Adverse Effects
Frequency Not Defined
Dizziness
Fatigue
Headache
Insomnia
Numbness
Rash
Diarrhea
Mild nausea
Vomiting
Chest pain
Diplopia
Nystagmus
Rare
- Ataxia
- Stevens-Johnson syndrome
- Gum hypertrophy
- Lymphadenopathy
- Megaloblastic anemia
- Systemic lupus erythematosus
Warnings
Contraindications
Hepatic abnormalities
Blood dyscrasias
Cautions
Use during pregnancy may result in incr incidence of birth defects in offspring (fetal hydantoin syndrome); do not discontinue in pts with major seizures due to risk of status epilepticus with hypoxia & risk to mother & fetus
Possible risk of blood dyscrasias & lymphadenopathy
May interfere with folic acid metabolism, causing megaloblastic anemia
Check LFT's if indicated; monitor blood counts & UA at initiation & monthly for several months
Pregnancy & Lactation
Pregnancy Category: D
Lactation: enters breast milk/not recommended
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Half-Life: 3-9 hr
Metabolism: by liver to p-hydroxylated & m-hydroxylated derivatives following N-deethylation; these metabolites are conjugated with glucuronic acid
Excretion: urine, feces
Mechanism of Action
Exerts an antiepileptic effect w/o causing general CNS depression. Mechanism of action probably similar to phenytoin but less effective & less toxic than phenytoin
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Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.
