loss of therapeutic effect.gotu kolaMonitor Closely (1)gotu kola increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.griseofulvinMinor (1)pentobarbital decreases levels of griseofulvin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.guanfacineMonitor Closely (1)pentobarbital will decrease the level or effect of guanfacine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Strong or moderate CYP3A4 inducers significantly reduce guanfacine plasma concentrations and elimination half-life. If coadministered, more frequent dosing of the IR product may be required to achieve or maintain the desired hypotensive response. For patients with ADHD, FDA-approved labeling for ER guanfacine recommends that, if coadministered, doubling the recommended dose of guanfacine should be considered.haloperidolMonitor Closely (1)pentobarbital and haloperidol both increase sedation. Use Caution/Monitor.Minor (1)haloperidol, pentobarbital. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hyperthermia if haloperidol admin. during barbiturate withdrawal.hawthornMonitor Closely (1)hawthorn increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.heminMonitor Closely (1)pentobarbital decreases effects of hemin by pharmacodynamic antagonism. Use Caution/Monitor. Drugs that increase delta-aminolevulinic acid synthetase may decrease hemin effect.heparinSerious - Use Alternative (1)pentobarbital decreases effects of heparin by increasing metabolism. Avoid or Use Alternate Drug.hopsMonitor Closely (1)hops increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.hydrocodoneMonitor Closely (1)pentobarbital will decrease the level or effect of hydrocodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Caution when discontinuing CYP3A4 inducers that are coadministered with hydrocodone; plasma concentrations of hydrocodone may increase and can result in potentially fatal respiratory depressionSerious - Use Alternative (1)hydrocodone, pentobarbital. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.hydrocortisoneMonitor Closely (1)pentobarbital will decrease the level or effect of hydrocortisone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.hydromorphoneMonitor Closely (1)pentobarbital and hydromorphone both increase sedation. Use Caution/Monitor.hydroxyprogesterone caproate (DSC)Monitor Closely (1)pentobarbital will decrease the level or effect of hydroxyprogesterone caproate (DSC) by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.hydroxyzineMonitor Closely (1)hydroxyzine and pentobarbital both increase sedation. Use Caution/Monitor.ibrutinibSerious - Use Alternative (1)pentobarbital decreases levels of ibrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Strong CYP3A inducers decrease ibrutinib plasma concentrations by ~10-fold.ibuprofenMinor (1)pentobarbital will decrease the level or effect of ibuprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.ibuprofen IVMinor (1)pentobarbital will decrease the level or effect of ibuprofen IV by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.idelalisibSerious - Use Alternative (1)pentobarbital will decrease the level or effect of idelalisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration; strong CYP3A4 inducers significantly decrease idelalisib systemic exposureifosfamideMonitor Closely (2)pentobarbital increases effects of ifosfamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor. Coadministration of ifosfamide with CYP2B6 inducers may increase metabolism of ifosfamide to its metabolite. Monitor for increased effects/toxicities if combined with CYP2B6 inducers. pentobarbital increases toxicity of ifosfamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inducers may increase the metabolism of ifosfamide to its active alkylating metabolites. CYP3A4 inducers may increase the formation of the neurotoxic/nephrotoxic ifosfamide metabolite, chloroacetaldehyde. Closely monitor patients taking ifosfamide with CYP3A4 inducers for toxicities and consider dose adjustment.iloperidoneMonitor Closely (2)pentobarbital will decrease the level or effect of iloperidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. pentobarbital and iloperidone both increase sedation. Use Caution/Monitor.imatinibMinor (1)pentobarbital will decrease the level or effect of imatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.imipramineMonitor Closely (4)pentobarbital will decrease the level or effect of imipramine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. pentobarbital will decrease the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. pentobarbital will decrease the level or effect of imipramine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. pentobarbital and imipramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, imipramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.indinavirMonitor Closely (1)pentobarbital will decrease the level or effect of indinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.infigratinibSerious - Use Alternative (1)pentobarbital will decrease the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.irinotecanMonitor Closely (1)pentobarbital will decrease the level or effect of irinotecan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.irinotecan liposomalMonitor Closely (1)pentobarbital will decrease the level or effect of irinotecan liposomal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.isavuconazonium sulfateContraindicated (1)pentobarbital will decrease the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.isocarboxazidSerious - Use Alternative (1)isocarboxazid, pentobarbital. Other (see comment). Contraindicated. Comment: CNS depressants such as barbiturates should not be used in combination with isocarboxazid.Minor (1)isocarboxazid increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.isoproterenolMonitor Closely (1)pentobarbital increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.isradipineMinor (1)pentobarbital will decrease the level or effect of isradipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.istradefyllineSerious - Use Alternative (1)pentobarbital will decrease the level or effect of istradefylline by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of istradefylline with strong CYP3A4 inducers.itraconazoleMinor (2)pentobarbital will decrease the level or effect of itraconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. pentobarbital decreases levels of itraconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ivabradineSerious - Use Alternative (1)pentobarbital will decrease the level or effect of ivabradine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ivabradine with moderate CYP3A4 inducers.ivacaftorSerious - Use Alternative (1)pentobarbital decreases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with strong CYP3A4 inducers; systemic exposure of ivacaftor substantially reduced (ie, ~9-fold).ivosidenibSerious - Use Alternative (1)pentobarbital will increase the level or effect of ivosidenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of ivosidenib with strong CYP3A4 inducers decreased ivosidenib plasma concentrations.ixabepiloneMonitor Closely (1)pentobarbital will decrease the level or effect of ixabepilone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ixazomibSerious - Use Alternative (1)pentobarbital will decrease the level or effect of ixazomib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ixazomib with strong CYP3A inducers. Strong inducers have been shown to decrease ixazomib Cmax by 54% and AUC by 74%.kavaMonitor Closely (1)kava increases effects of pentobarbital by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.ketamineMonitor Closely (1)ketamine and pentobarbital both increase sedation. Use Caution/Monitor.ketoconazoleMinor (2)pentobarbital will decrease the level or effect of ketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. pentobarbital decreases levels of ketoconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ketotifen, ophthalmicMonitor Closely (1)pentobarbital and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.labetalolMonitor Closely (1)pentobarbital decreases levels of labetalol by increasing metabolism. Use Caution/Monitor. Consider a higher beta-blocker dose during coadministration of pentobarbital. Atenolol, sotalol, nadolol less likely to be affected than other beta blockers.lansoprazoleMinor (1)pentobarbital will decrease the level or effect of lansoprazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.lapatinibMonitor Closely (1)pentobarbital will decrease the level or effect of lapatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.larotrectinibSerious - Use Alternative (1)pentobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-liveslasmiditanMonitor Closely (1)lasmiditan, pentobarbital. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.lefamulinSerious - Use Alternative (1)pentobarbital will decrease the level or effect of lefamulin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lefamulin with strong or moderate CYP3A inducers unless the benefit outweighs risks. Monitor for reduced efficacy.lemborexantSerious - Use Alternative (2)pentobarbital will decrease the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. lemborexant, pentobarbital. Either increases effects of the other by sedation. Avoid or Use Alternate Drug. Use of lemborexant with other drugs to treat insomnia is not recommended.lenacapavirSerious - Use Alternative (1)pentobarbital will decrease the level or effect of lenacapavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lenacapavir with moderate CYP3A4 inducers.leniolisibSerious - Use Alternative (1)pentobarbital will decrease the level or effect of leniolisib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.levalbuterolMonitor Closely (1)pentobarbital increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.levamlodipineMonitor Closely (1)pentobarbital will decrease the level or effect of levamlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No information is available on the quantitative effects of CYP3A4 inducers on amlodipine. Closely monitor blood pressure when amlodipine is coadministered with CYP3A4 inducers.levoketoconazoleMinor (2)pentobarbital will decrease the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. pentobarbital decreases levels of levoketoconazole by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.levonorgestrel intrauterineMonitor Closely (1)pentobarbital decreases levels of levonorgestrel intrauterine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.levonorgestrel oralMonitor Closely (1)pentobarbital decreases levels of levonorgestrel oral by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.levonorgestrel oral/ethinylestradiol/ferrous bisglycinateMonitor Closely (1)pentobarbital will decrease the level or effect of levonorgestrel oral/ethinylestradiol/ferrous bisglycinate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. The efficacy of hormonal contraceptives may be reduced. Use an alternative method of contraception or a backup method when enzyme inducers are used with combined hormonal contraceptives (CHCs), and continue backup contraception for 28 days after discontinuing enzyme inducer to ensure contraceptive reliability.levorphanolMonitor Closely (1)pentobarbital and levorphanol both increase sedation. Use Caution/Monitor.levothyroxineMinor (1)pentobarbital decreases levels of levothyroxine by increasing metabolism. Minor/Significance Unknown.lidocaineMonitor Closely (1)pentobarbital will decrease the level or effect of lidocaine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.linagliptinMonitor Closely (1)pentobarbital will decrease the level or effect of linagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Use of alternative treatments is strongly recommended when linagliptin is to be administered with a CYP3A4 inducerlinezolidMinor (1)linezolid increases levels of pentobarbital by decreasing metabolism. Minor/Significance Unknown. Theoretical interaction.liothyronineMinor (1)pentobarbital decreases levels of liothyronine by increasing metabolism. Minor/Significance Unknown.lisdexamfetamineMonitor Closely (1)pentobarbital increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.lofepramineMonitor Closely (1)pentobarbital and lofepramine both increase sedation. Use Caution/Monitor.Minor (1)pentobarbital, lofepramine. Other (see comment). Minor/Significance Unknown. Comment: Barbiturates may increase adverse effects, including respiratory depression, produced by toxic doses of TCAs. With therapeutic doses of TCAs, barbiturates increase metabolism and decrease blood concentrations of TCAs.lofexidineMonitor Closely (1)pentobarbital and lofexidine both increase sedation. Use Caution/Monitor.lonafarnibContraindicated (1)pentobarbital will decrease the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Lonafarnib is a sensitive CYP3A4 substrate. Coadministration with strong or moderate CYP3A4 inducers is contraindicated.lopinavirMonitor Closely (1)pentobarbital will decrease the level or effect of lopinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.loprazolamMonitor Closely (1)pentobarbital and loprazolam both increase sedation. Use Caution/Monitor.loratadineMonitor Closely (1)pentobarbital will decrease the level or effect of loratadine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.lorazepamMonitor Closely (1)pentobarbital and lorazepam both increase sedation. Use Caution/Monitor.lorlatinibContraindicated (1)pentobarbital will decrease the level or effect of lorlatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Coadministration of lorlatinib with strong CYP3A inducers is contraindicated. Discontinue the strong CYP3A inducer for 3 plasma half-lives before initiating lorlatinib.lormetazepamMonitor Closely (1)pentobarbital and lormetazepam both increase sedation. Use Caution/Monitor.losartanMinor (1)pentobarbital will decrease the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.lovastatinSerious - Use Alternative (1)pentobarbital will decrease the level or effect of lovastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.loxapineMonitor Closely (1)pentobarbital and loxapine both increase sedation. Use Caution/Monitor.loxapine inhaledMonitor Closely (1)pentobarbital and loxapine inhaled both increase sedation. Use Caution/Monitor.lumacaftor/ivacaftorContraindicated (1)pentobarbital will decrease the level or effect of lumacaftor/ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Strong CYP3A inducers have minimal effect on lumacaftor exposure, but decreased ivacaftor exposure (AUC) by