Barbiturates

Acebutolol, barbiturates

Concomitant administration may increase the blood pressure lowering effect of beta-blockers.

Acenocoumarol [1], barbiturates ---> SmPC of [1] of eMC

The co-administration may decrease the anticoagulant effect

Acetylsalicylic acid, barbiturates

The acetylsalicylic acid increases the barbiturate plasma levels

Alcohol, barbiturates

The co-administration may mutually enhance the CNS depressant effects

Alfacalcidol, barbiturates

The coadministration may require an increased dose of alfacalcidol to produce the desired effect.

Alfentanyl [1], barbiturates ---> SmPC of [1] of eMC

CNS depressants may enhance or prolong the respiratory depressant effects of alfentanil.

Alimemazine [1], barbiturates ---> SmPC of [1] of eMC

The sedative effects of phenothiazines may be intensified (additively) by barbiturates

Aliskiren/amlodipine/hydrochlorothiazide [1], barbiturates ---> SmPC of [1] of EMA

Concomitant administration of thiazide diuretics with subtances that also have a blood pressure lowering effect (e.g. by reducing sympathetic central nervous system activity or direct vasodilatation) may potentiate orthostatic hypotension.

Aliskiren/hydrochlorothiazide [1], barbiturates ---> SmPC of [1] of EMA

Concomitant administration of thiazide diuretics with subtances that also have a blood pressure lowering effect may potentiate orthostatic hypotension.

Alizapride, barbiturates

Increased CNS depressant effect

Amifampridine, barbiturates

Potent inducers of enzymes that metabolize medicinal products may increase amifampridine elimination and give rise to subtherapeutic exposure of amifampridine.

Amiloride, barbiturates

Increased hypotensive effect

Amiloride/hydrochlorothiazide [1], barbiturates ---> SmPC of [1] of eMC

Co-administration with barbiturates may potentiate orthostatic hypotension.

Aminophylline, barbiturates ---> SmPC of [theophylline] of eMC

The barbiturates increase clearance of theophylline and it may be necessary to increase dosage to ensure a therapeutic effect

Amisulpride [1], barbiturates ---> SmPC of [1] of eMC

Caution is advised when coadministering amisulpride with CNS depressants

Amitriptyline, barbiturates

The strong CYP3A4 induction may decrease the plasma concentrations of amitriptyline

Amlodipine/valsartan/hydrochlorothiazide [1], barbiturates ---> SmPC of [1] of EMA

Concomitant administration of thiazide diuretics with substances that also have a blood pressure lowering effect (e.g.by reducing sympathetic central nervous system activity or direct vasodilatation) may potentiate orthostatic hypotension.

Androgens, barbiturates

The enzymatic inductor may increase the metabolism of androgen and decrease its plasma levels and effect

Antihistamines, barbiturates

The co-administration may increase the CNS depressant effect

Antihypertensives, barbiturates

Orthostatic hypotension may be aggravated

Apraclonidine [1], barbiturates ---> SmPC of [1] of eMC

The possibility of an additive or potentiating effect with CNS depressants should be considered.

Atenolol, barbiturates

Concomitant use of atenolol with antihypertensive agents as well as other drugs with blood pressure lowering potential may increase the risk of hypotension.

Atenolol/chlortalidone, barbiturates

Enhanced antihypertensive effect

Atenolol/nifedipine [1], barbiturates ---> SmPC of [1] of eMC

Concomitant use of atenolol with antihypertensive agents as well as other drugs with blood pressure lowering potential may increase the risk of hypotension.

Baclofen [1], barbiturates ---> SmPC of [1] of eMC

The concomitant administration of baclofen and other medications that have a suppressing effect on functions of the central nervous system can enhance the action of baclofen

Barbiturates [1], lofepramine ---> SmPC of [1] of eMC

Effects of lofepramine may be potentiated when administered with CNS depressant substances

Barbiturates [1], thioridazine ---> SmPC of [1] of eMC

Concomitant use of barbiturates with phenothiazines may result in reduced serum levels of both drugs, and an increased response if one of the drugs is withdrawn.

Barbiturates, beclometasone

The enzymatic induction may increase the metabolism and decrease the plasma concentrations of corticosteroid

Barbiturates, bendroflumethiazide

Postural hypotension may be enhanced by barbiturates

Barbiturates, benperidol [2] ---> SmPC of [2] of eMC

The dosage of anti-convulsants may need to be increased to take account of the lowered seizure threshold.

Barbiturates, benzodiazepines

Enhancement of the central depressive effect may occur if benzodiazepines are combined with centrally-acting drugs

Barbiturates, betablockers ---> SmPC of [nebivolol] of eMC

Concomitant use may enhance the hypotensive effect of the beta-blockers (additive effect).

Barbiturates, betaxolol

The combination may cause strong hypotension

Barbiturates, bisoprolol [2] ---> SmPC of [2] of eMC

Concomitant use of bisoprolol with antihypertensive agents as well as with other medicinal products with blood pressure lowering potential may increase the risk of hypotension.

Barbiturates, brimonidine [2] ---> SmPC of [2] of EMA

The possibility of an additive or potentiating effect with CNS depressants should be considered.

Barbiturates, brinzolamide/brimonidine [2] ---> SmPC of [2] of EMA

Caution is advised due to the possibility of an additive or potentiating effect of brinzolamide/brimonidine with CNS depressants

Barbiturates, bromelain

Bromelain may increase drowsiness caused by some medicinal products

Barbiturates, bromperidol

The enzymatic induction may decrease the plasma levels of bromperidol

Barbiturates, buprenorphine [2] ---> SmPC of [2] of EMA

This combination increases central nervous system depression.

Barbiturates, buprenorphine/naloxone [2] ---> SmPC of [2] of EMA

The combination increases the central nervous system depression

Barbiturates, caffeine

Caffeine antagonizes the sedative effects. Increased caffeine elimination

Barbiturates, calcifediol

Enzym inductors may decrease plasma levels of calcifediol

Barbiturates, calcitriol

The enzymatic induction may decrease the levels of calcitriol.

Barbiturates, calcium carbonate/cholecalciferol ---> SmPC of [cholecalciferol] of eMC

The co-administration may increase the metabolism and decrease the effect of vitamin D3

Barbiturates, canagliflozin [2] ---> SmPC of [2] of EMA

Enzyme inducers may give rise to decreased exposure of canagliflozin. These decreases in exposure to canagliflozin may decrease efficacy.

Barbiturates, canagliflozin/metformin [2] ---> SmPC of [2] of EMA

Enzyme inducers may give rise to decreased exposure of canagliflozin. These decreases in exposure to canagliflozin may decrease efficacy.

Barbiturates, carisoprodol

The co-administration may enhance the depressive effect on the central nervous system.

Barbiturates, carvedilol [2] ---> SmPC of [2] of eMC

The co-administration may increase the hypotensive effect and the enzymatic induction may decrease the plasma levels of carvedilol

Barbiturates, celecoxib [2] ---> SmPC of [2] of EMA

Concomitant use of inducers of celecoxib with CYP2C9 may reduce plasma concentrations of celecoxib.

Barbiturates, celiprolol [2] ---> SmPC of [2] of eMC

Concomitant use may potentiate the orthostatic hypotensive effects of beta blockers.

Barbiturates, chloramphenicol

Cloramfenicol prolongs the effect of barbiturate

Barbiturates, chlordiazepoxide [2] ---> SmPC of [2] of eMC

When used concurrently chlordiazepoxide and anti-epileptic drugs, side effects and toxicity may be more evident, particularly with hydantoins (e.g. phenytoin) and/or barbiturates.

Barbiturates, chlormadinone

The co-administration increases the metabolism and decreases the plasma levels of gestagen

Barbiturates, chlorpromazine [2] ---> SmPC of [2] of eMC

The co-administration may increase the CNS depressant effect

Barbiturates, chlorprothixene

The co-administration of chlorprothixene with CNS depressants may cause strong sedation or respiratory depression

Barbiturates, chlortalidone

The co-administration may increase the antihypertensive effects

Barbiturates, cholecalciferol [2] ---> SmPC of [2] of eMC

The co-administration may increase the metabolism and decrease the effect of vitamin D3

Barbiturates, cholestyramine

Decreased absorption. Patients should take other drugs at least 1 hour before or 4-6 hours after colestyramine to minimize possible interference with their absorption.

Barbiturates, cinnarizine [2] ---> SmPC of [2] of eMC

Concurrent use of cinnarizine and CNS depressants may potentiate the sedative effects

Barbiturates, clomipramine [2] ---> SmPC of [2] of eMC

CYP3A and CYP2C inducers may decrease clomipramine levels as co-administration of drugs known to induce cytochrome P450 enzymes, principally CYP3A4, CYP2C19 may accelerate the metabolism and decrease the efficacy of clomipramine

Barbiturates, clonazepam

The enzymatic induction may decrease the plasma levels of clonazepam

Barbiturates, clopamide

Increased hypotensive effect

Barbiturates, cloperastine

Increased CNS depressant effect

Barbiturates, cloprednol

The strong CYP3A4 induction may decrease the plasma concentrations of cloprednol

Barbiturates, CNS depressants

The co-administration may mutually enhance the CNS depressant effects

Barbiturates, corticosteroids

The enzymatic induction may increase the metabolism and decrease the plasma concentrations of corticosteroid

Barbiturates, cotrimoxazole

The administration of barbiturates increases toxicity of cotrimoxazole

Barbiturates, cyclosporine [2] ---> SmPC of [2] of eMC

All inducers of CYP3A4 and/or P-glycoprotein are expected to decrease ciclosporin levels.

Barbiturates, cyproterone/ethinylestradiol [2] ---> SmPC of [2] of eMC

Drugs which induce hepatic enzymes (especially cytochrome P450 3A4) increase the metabolism of contraceptive steroids and hence may result in breakthrough bleeding and pregnancy.

Barbiturates, darifenacin [2] ---> SmPC of [2] of EMA

Substances that are inducers of CYP3A4 are likely to decrease the plasma concentrations of darifenacin.

Barbiturates, deflazacort

The strong CYP3A4 induction may decrease the plasma concentrations of glucocorticoid

Barbiturates, desogestrel [2] ---> SmPC of [2] of eMC

Interactions can occur with medicinal products that induce microsomal enzymes, which can result in increased clearance of sex hormones

Barbiturates, dexchlorpheniramine

The combination of dexchlorpheniramine with other CNS depressants may enhance the CNS depressant effect

Barbiturates, dextromethorphan

The co-administration of dextromethorphan with CNS depressants can result in mutual potentiation of effects

Barbiturates, diazoxide

Diazoxide may potentiate the effect of hypotensive drugs, what cause a further hypotension

Barbiturates, dienogest

The enzymatic induction may decrease the plasma levels of dienogest

Barbiturates, digitoxin

The strong CYP3A4 induction may decrease the plasma concentrations of digitoxin

Barbiturates, dimenhydrinate

Dimenhydrinate may increase the effects of other CNS depressors and enhance the sedative effects

Barbiturates, dipotassium clorazepate

The combination of CNS depressors may mutually potentiate the depressor effect on the CNS

Barbiturates, disulfiram

Disulfiram inhibits the metabolism of many drugs which are converted in the liver and thereby enhances efficacy.

Barbiturates, doxepin

Barbiturates may increase the rate of metabolism of doxepin.

Barbiturates, doxorubicine [2] ---> SmPC of [2] of eMC

Concomitant administration of doxorubicin with inducers of CYP450 might decrease plasma concentrations of doxorubicin and reduce efficacy.

Barbiturates, doxycycline

The enzymatic inductor may decrease the plasma levels of doxycycline

Barbiturates, doxylamine

Antihistaminic agents have additive effects with other CNS depressants

Barbiturates, droperidol [2] ---> SmPC of [2] of eMC

Droperidol may potentiate the action of sedatives

Barbiturates, drospirenone/estetrol [2] ---> SmPC of [2] of EMA

Medicinal products increasing the clearance of CHCs

Barbiturates, dydrogesterone

The enzymatic induction may decrease the plasma levels of dydrogesterone

Barbiturates, enalapril/hydrochlorothiazide [2] ---> SmPC of [2] of eMC

Potentiation of orthostatic hypotension may occur.

Barbiturates, erlotinib [2] ---> SmPC of [2] of EMA

Erlotinib is metabolised in the liver by the hepatic cytochromes in humans, primarily CYP3A4 and to a lesser extent by CYP1A2. Potent inducers of CYP3A4 activity increase erlotinib metabolism and significantly decrease erlotinib plasma concentrations.

Barbiturates, esketamine

Prolongation of awakening phase

Barbiturates, esmolol [2] ---> SmPC of [2] of eMC

Concomitant administration of esmolol and barbiturates may increase the blood pressure lowering effect.

Barbiturates, estriol [2] ---> SmPC of [2] of eMC

The metabolism of estrogens may be increased by concomitant use of substances known to induce drug-metabolising enzymes, specifically cytochrome P450 enzymes

Barbiturates, estrogens

The metabolism of estrogens may be increased by concomitant use of substances known to induce drug-metabolising enzymes, specifically cytochrome P450 enzymes

Barbiturates, ethinyl estradiol

Interactions can occur with drugs that induce hepatic enzymes which can result in increased clearance of sex hormones

Barbiturates, ethinylestradiol/chlormadinone

Interactions can occur with drugs that induce hepatic enzymes which can result in increased clearance of sex hormones

Barbiturates, ethinylestradiol/desogestrel [2] ---> SmPC of [2] of eMC

Interactions can occur with drugs that induce microsomal enzymes, which can result in increased clearance of sex hormones

Barbiturates, ethinylestradiol/drospirenone [2] ---> SmPC of [2] of eMC

Interactions can occur with drugs that induce hepatic enzymes which can result in increased clearance of sex hormones

Barbiturates, ethinylestradiol/etonogestrel [2] ---> SmPC of [2] of eMC

Interactions can occur with drugs that induce hepatic enzymes which can result in increased clearance of sex hormones

Barbiturates, ethinylestradiol/gestodene [2] ---> SmPC of [2] of eMC

Drugs which induce hepatic enzymes (especially cytochrome P450 3A4) increase the metabolism of contraceptive steroids and hence may result in breakthrough bleeding and pregnancy.

Barbiturates, ethinylestradiol/norgestimate [2] ---> SmPC of [2] of eMC

Drugs or herbal products that induce enzymes, especially CYP3A4, may decrease the plasma concentrations of contraceptive hormones, and may decrease their effectiveness and/or increase breakthrough bleeding.

Barbiturates, ethyl loflazepate

The co-administration may cause a mutual potentiation of the depressor effect on the CNS

Barbiturates, felodipine ---> SmPC of [felodipine/metoprolol] of eMC

The enzymatic induction may decrease the plasma levels of felodipine

Barbiturates, felodipine/metoprolol

It has been shown that inductors of cytochrome P450-3A4 system decrease the plasma concentrations of felodipine. The concomitant use with strong CYP3A4 inductors should be avoided

Barbiturates, fludrocortisone [2] ---> SmPC of [2] of eMC

Increased metabolic clearance of fludrocortisone. Patients should be carefully observed for possible diminished effect of steroid, and the dosage should be adjusted accordingly.

Barbiturates, fluocortolone

The strong CYP3A4 induction may decrease the plasma concentrations of fluocortolone

Barbiturates, fluoxymesterone

The enzymatic inductor may increase the metabolism of fluoxymesterone and decrease its plasma levels and effect

Barbiturates, flupentixol

The enzymatic induction may decrease the plasma levels of flupentixol

Barbiturates, fluphenazine [2] ---> SmPC of [2] of eMC

Concomitant use of barbiturates with phenothiazines may result in reduced serum levels of both drugs, and an increased response if one of the drugs is withdrawn.

Barbiturates, flurazepam [2] ---> SmPC of [2] of eMC

When flurazepam is used in conjunction with anti-epileptic drugs, side-effects and toxicity may be more evident, particularly with hydantoins or barbiturates

Barbiturates, fluspirilene

The enzymatic induction may decrease the plasma levels of neuroleptic agent

Barbiturates, gefitinib [2] ---> SmPC of [2] of EMA

Substances that are inducers of CYP3A4 activity may increase metabolism and decrease gefitinib plasma concentrations and thereby reduce the efficacy of gefitinib. Concomitant medicinal products that induce CYP3A4 should be avoided.

Barbiturates, gestagens

The enzymatic induction may decrease the plasma levels of progestagen

Barbiturates, glibenclamide

The co-administration may weaken the hypoglycemic effect

Barbiturates, glimepiride [2] ---> SmPC of [2] of eMC

Weakening of the blood-glucose-lowering effect and possible hyperglycaemia

Barbiturates, gliquidone

Hyperglycemic reactions may occur as expression of weakening effect of gliquidone with gliquidone is co-administered with barbiturates

Barbiturates, griseofulvin

Decreased griseofulvin effect

Barbiturates, guanfacin [2] ---> SmPC of [2] of EMA

Caution should be used when Intuniv is administered concomitantly with CNS depressant medicinal products due to the potential for additive pharmacodynamic effects such as sedation and somnolence.

Barbiturates, hemine [2] ---> SmPC of [2] of eMC

The metabolism of concomitantly administered drugs that are metabolised by cytochrome P450 enzymes may increase during administration of hemin, leading to lower systemic exposure.

Barbiturates, hydrochlorothiazide ---> SmPC of [amlodipine/valsartan/hydrochlorothiazide] of EMA

Concomitant administration of thiazide diuretics with substances that also have a blood pressure lowering effect (e.g.by reducing sympathetic central nervous system activity or direct vasodilatation) may potentiate orthostatic hypotension.

Barbiturates, hydrocortisone [2] ---> SmPC of [2] of EMA

Potent CYP 3A4 inducers can enhance the metabolic clearance of cortisol, decrease terminal half-life and thus reduce circulating levels and increase fluctuations of cortisol (due to shorter terminal half-life).

Barbiturates, hydroxyzine [2] ---> SmPC of [2] of eMC

Patients should be warned that hydroxyzine may enhance their response to barbiturates

Barbiturates, IMAOs

The MAOI may enhance the effects of barbiturate

Barbiturates, imipramine [2] ---> SmPC of [2] of eMC

Imipramine may potentiate the CNS depressant effects of central depressant drugs. The barbiturate may activate the hepatic mono-oxygenase enzyme system and lower plasma concentrations of imipramine, resulting in decreased efficacy

Barbiturates, isocarboxazid

Concurrent administration of isocarboxazid with other central nervous system depressants may lead to potentiation of their effects.

Barbiturates, isoniazid

Isoniazid, enzymatic inhibitor, may increase the plasma levels of barbiturate

Barbiturates, ivabradine [2] ---> SmPC of [2] of EMA

Ivabradine is metabolised by CYP3A4 only. CYP3A4 inducers may decrease ivabradine exposure and activity. The concomitant use of CYP3A4 inducing medicinal products may require an adjustment of the dose of ivabradine.

Barbiturates, kebuzone

Kebuzone can enhance the hypnotic effect. The barbiturate may decrease the effect of kebuzone

Barbiturates, ketamine [2] ---> SmPC of [2] of eMC

Prolonged recovery time may occur if barbiturates are used concurrently with ketamine.

Barbiturates, lacidipine

It has been shown that the plasma levels of other dihydropyridines are decreased with the co-administration of enzymatic inductors

Barbiturates, lasofoxifene

Lasofoxifene clearance may be increased in patients chronically treated with inducers of CYP3A4 and may result in reduced efficacy

Barbiturates, levobunolol

The co-administration may have an additive effect

Barbiturates, levomepromazine

The co-administration of levomepromazine with other central nervous depressants will cause a greater depressant effect on central nervous system

Barbiturates, levomethadone

Enhancement of effects and adverse effects, particularly respiratory depression

Barbiturates, levonorgestrel [2] ---> SmPC of [2] of eMC

The metabolism of levonorgestrel is enhanced by concomitant use of liver enzyme inducers.

Barbiturates, levonorgestrel/ethinylestradiol [2] ---> SmPC of [2] of eMC

Interactions of enzyme inducers with oral contraceptives may lead to breakthrough bleeding and/or contraceptive failure: Women should temporarily use a barrier method in addition to the COC or choose another method of contraception.

Barbiturates, levothyroxine [2] ---> SmPC of [2] of eMC

Metabolism of levothyroxine (thyroxine) accelerated by barbiturates. (may increase requirements for levothyroxine (thyroxine) in hypothyroidism)

Barbiturates, lidocaine

Concomitant use of lidocaine and CNS depressants may cause additive depressor effect. Special caution is recommended

Barbiturates, liothyronine

The enzymatic induction may decrease the plasma levels and the effect of liothyronine.

Barbiturates, loop diuretics

Enhancement of hypotensive effect

Barbiturates, lorazepam [2] ---> SmPC of [2] of eMC

Enhancement of the central depressive effect may occur if lorazepam is combined with other CNS depressants

Barbiturates, lormetazepam

The benzodiazepines, including lormetazepam produce additive CNS depressant effects when co-administered with other medications which themselves produce CNS depression

Barbiturates, losartan/hydrochlorothiazide [2] ---> SmPC of [2] of eMC

Potentiation of orthostatic hypotension may occur.

Barbiturates, lymecycline

Concurrent use of barbiturates may decrease plasma levels of tetracyclines.

Barbiturates, maprotiline

Barbiturate may decrease plasma levels of maprotiline

Barbiturates, medroxyprogesterone ---> SmPC of [estradiol] of eMC

The metabolism of progestogens may be increased by concomitant administration of compounds known to induce drug-metabolising enzymes, specifically cytochrome P450 enzymes.

Barbiturates, mefruside

The co-administration may increase the antihypertensive effects

Barbiturates, megestrol

Accelerated metabolism of barbiturates

Barbiturates, melperone

An enhancement of the central depressive effect may occur in cases of combination of melperone with other central depressive drugs

Barbiturates, memantin [2] ---> SmPC of [2] of EMA

Decreased effect of the barbiturate

Barbiturates, mephenytoin

Decreased hydantoin plasma levels

Barbiturates, mequitazine

Central nervous system depressants may enhance the sedative effects of mequitazine

Barbiturates, mesterolone

The enzymatic inductor may increase the metabolism of mesterolone and decrease its plasma levels and effect

Barbiturates, methadone

The co-administration may accelerate the metabolism of methadone, decrease its plasma levels and precipitate a withdrawal syndrome

Barbiturates, methocarbamol

Methocarbamol may potentiate the effects of other central nervous system depressants and stimulants

Barbiturates, methotrexate [2] ---> SmPC of [2] of EMA

Displacement of methotrexate from serum albumin binding and thus increase bioavailability (indirect dose increase).

Barbiturates, methyldopa

The antihypertensive effect of methyldopa may be diminished

Barbiturates, methylprednisolone

The strong CYP3A4 induction may decrease the plasma concentrations of glucocorticoid

Barbiturates, metildigoxin

Effect weakening of metildigoxin

Barbiturates, metoclopramide

The co-administration may mutually enhance the sedative effects of the CNS. The combination requires caution

Barbiturates, metolazone

The co-administration may enhance the risk of orthostatic hypotension

Barbiturates, metronidazole

Decreased metronidazole effect

Barbiturates, midazolam [2] ---> SmPC of [2] of EMA

The co-administration of midazolam with other sedative/hypnotic agents and CNS depressants, including alcohol, is likely to result in enhanced sedation and respiratory depression.

Barbiturates, minocycline [2] ---> SmPC of [2] of EMA

The enzymatic inductor may increase the metabolism of minocycline and decrease its plasma levels

Barbiturates, nabilone

Nabilone should be administered with caution to patients who are taking other CNS depressants

Barbiturates, nalbuphine

Other central nervous system depressant drugs may increase the risk of respiratory depression, which can be life-threatening in the case of an overdose

Barbiturates, naloxone

With the usual dose of naloxone there is no interaction with barbiturates

Barbiturates, nebivolol [2] ---> SmPC of [2] of eMC

Concomitant use may enhance the hypotensive effect of the beta-blockers (additive effect).

Barbiturates, neostigmine

Neostigmine may enhance the effects of barbiturate

Barbiturates, neuroleptics

Potentiation may occur if antipsychotic drugs are combined with CNS depressants

Barbiturates, nomegestrol

The enzymatic inductor may increase the metabolism of nomegestrol and decrease its plasma levels

Barbiturates, norethisterone

The enzymatic induction may decrease the plasma levels and the effect of progestagen

Barbiturates, norethisterone acetate

Reduced contraceptive efficacy with hepatic enzyme-inducing drugs

Barbiturates, norethisterone enantate [2] ---> SmPC of [2] of eMC

Reduced contraceptive efficacy with hepatic enzyme-inducing drugs

Barbiturates, norgestimate

The CYP3A4 induction may accelerate the norgestimate metabolism and decrease its plasma levels and effect. The induction lasts at least 4 weeks after dose interruption

Barbiturates, norgestrel

The enzymatic induction may accelerate the metabolism of steroid hormones and decrease their plasma levels and effect.

Barbiturates, nortriptyline [2] ---> SmPC of [2] of eMC

Barbiturates may increase the rate of metabolism of nortriptyline.

Barbiturates, opiates ---> SmPC of [alfentanyl] of eMC

The co-administration may enhance or prolong the respiratory depressant effect of opioid.

Barbiturates, opipramol

The barbiturate, enzymatic inductor, may increase the antidepressant metabolism and decrease its effect. Opipramol may potentiate the effects of other CNS depressants

Barbiturates, oral anticoagulants

Barbiturate, enzymatic inductor, may increase the metabolism of the oral anticoagulant and decrease its plasma levels and effect

Barbiturates, oral contraceptives ---> SmPC of [ethinylestradiol/desogestrel] of eMC

The enzymatic induction may accelerate the metabolism of steroid hormones and decrease their plasma levels and effect.

Barbiturates, ornidazole

The enzymatic inductor may increase the metabolism of ornidazole and decrease its plasma levels

Barbiturates, oxatomide

The co-administration may increase the CNS depressant effect

Barbiturates, oxazepam

The co-administration may decrease the plasma levels of oxazepam

Barbiturates, oxomemazine

Enhancement of CNS depressant effect

Barbiturates, oxprenolol

The co-administration may enhance the hypotensive effect

Barbiturates, paracetamol

The enzymatic inductor may decrease the plasma levels of paracetamol and increase its hepatotoxicity. Caution is recommended

Barbiturates, perazine

The enzymatic inductor may increase the metabolism of perazine and decrease its plasma levels

Barbiturates, periciazine

Mutual enhancement of effects

Barbiturates, perphenazine

The enzymatic inductor may increase the metabolism of perphenazine and decrease its plasma levels

Barbiturates, pethidine [2] ---> SmPC of [2] of eMC

The central depressant effects of pethidine may be potentiated by the concurrent use of other CNS depressants; respiratory depression and profound sedation or coma may occur.

Barbiturates, phenazone

The enzymatic inductor may increase the metabolism of phenazone and decrease its plasma levels

Barbiturates, phenelzine [2] ---> SmPC of [2] of eMC

Phenelzine may potentiate the action of barbiturates

Barbiturates, phenothiazines ---> SmPC of [fluphenazine] of eMC

Concomitant use of barbiturates with phenothiazines may result in reduced serum levels of both drugs, and an increased response if one of the drugs is withdrawn.

Barbiturates, phenprocoumon

Weakening of phenprocoumon effect with the use concomitant or prior of barbiturates

Barbiturates, phenylbutazone

The co-administration may decrease the effect of phenylbutazone

Barbiturates, pholcodine

Pholcodine may enhance the sedative effect of central nervous system depressants

Barbiturates, pimozide [2] ---> SmPC of [2] of eMC

As with other neuroleptics, pimozide may increase the central nervous system depression produced by other CNS depressant drugs

Barbiturates, pindolol [2] ---> SmPC of [2] of eMC

Concomitant use may enhance the hypotensive effect of the beta-blockers (additive effect).

Barbiturates, pindolol/clopamide

Concomitant use of pindolol/clopamide and barbiturates may increase the blood pressure lowering effect.

Barbiturates, pioglitazone/glimepiride [2] ---> SmPC of [2] of EMA

Weakening of the blood-glucose-lowering effect and, thus raised blood glucose levels may occur

Barbiturates, pipamperone

Potentiation of the depressor effect on the CNS. The enzymatic inductor may increase the metabolism of pipamperone and decrease its plasma levels and effect

Barbiturates, pipotiazine [2] ---> SmPC of [2] of eMC

The CNS depressant actions of neuroleptic agents may be intensified (additively) by barbiturates. Respiratory depression may occur

Barbiturates, piretanide

The hypotensor effect of piretanide may be potentiated

Barbiturates, piritramide

The co-administration may enhance the adverse effects of piritramide, particularly respiratory depression

Barbiturates, prazepam

Concomitant use of prazepam and other CNS depressant drugs can mutually enhance the effects

Barbiturates, prednisolone

The co-administration may decrease the effect of prednisolone

Barbiturates, primidone

The CNS depressant effect of primidone is additive to those of other CNS depressants

Barbiturates, probenecide

Probenecid increases the exposure to barbiturate

Barbiturates, procarbazine

Procarbazine may enhance the effect of barbiturates

Barbiturates, progesterone

The enzymatic inductor may increase the metabolism of progesterone and decrease its plasma levels

Barbiturates, promazine

The concomitant administration of promazine with central nervous system depressants (including alcohol and anaesthetics) may result in accentuation of their effects

Barbiturates, promethazine

The co-administration of promethazine and other central nervous depressants can mutually enhance the effects and adverse reactions (particularly sedation and hypotension)

Barbiturates, propafenone

The barbiturate, strong CYP3A4 inductor, may decrease the plasma concentrations of propafenone and its antiarrhythmic effect

Barbiturates, propranolol [2] ---> SmPC of [2] of eMC

The metabolism of propranolol may be increased by potent liver enzyme inducer barbiturates.

Barbiturates, proteolytic enzymes enriched in bromelain [2] ---> SmPC of [2] of EMA

Bromelain may increase drowsiness caused by some medicinal products

Barbiturates, prothionamide

Protionamide delays the metabolism of barbiturates

Barbiturates, protirelin

Reduction of TSH-increase

Barbiturates, pyridostigmine

Pyridostigmine may enhance the effect of barbiturate

Barbiturates, quinapril [2] ---> SmPC of [2] of eMC

Barbiturates may potentiate orthostatic hypotension

Barbiturates, quinine [2] ---> SmPC of [2] of eMC

Suboptimal quinine serum levels may result from concomitant use of CYP3A4 inducers

Barbiturates, repaglinide [2] ---> SmPC of [2] of EMA

Barbiturates may reduce the hypoglycaemic effect of repaglinide

Barbiturates, rifabutin

Rifabutin has a similar structure as rifampicin. Concomitant use of rifabutin and barbiturates may decrease the barbiturate effects

Barbiturates, rifampicin [2] ---> SmPC of [2] of eMC

Rifampicin is a potent inducer of certain cytochrome P-450 enzymes. Coadministration of rifampicin with drugs that are also metabolised through these cytochrome P-450 enzymes may accelerate the metabolism and reduce the activity of these other drugs.

Barbiturates, silodosin [2] ---> SmPC of [2] of EMA

Silodosin is metabolised extensively, mainly via CYP3A4, alcohol dehydrogenase and UGT2B7. Substances that induce these enzymes may affect the plasma concentrations of silodosin and its active metabolite.

Barbiturates, somatostatin

Somatostatin prolongs the hypnotic effect of barbiturates. Co-administration is not recommended

Barbiturates, sotalol

The combination may enhance the hypotensive effect

Barbiturates, spironolactone

Barbiturates may enhance an orthostatic hypotension

Barbiturates, steroids

The enzymatic induction increases the steroid metabolism and decreases its effect

Barbiturates, sufentanil [2] ---> SmPC of [2] of EMA

The concomitant use of CNS depressants including barbiturates, benzodiazepines, neuroleptics or other opioids, halogen gases or other non-selective CNS depressants (e.g. alcohol) may enhance respiratory depression.

Barbiturates, sulfonylureas

Weakening of the blood-glucose-lowering effect and, thus raised blood glucose levels may occur

Barbiturates, sulpiride

Sulpiride enhances the sedative effect of barbiturate

Barbiturates, sultiame

The co-administration may increase the plasma levels of barbiturate. Adjustment of the dose may be required

Barbiturates, talinolol

The co-administration may cause a pronounced hypotension

Barbiturates, tapentadol [2] ---> SmPC of [2] of eMC

The co-administration may increase the risk of respiratory depression

Barbiturates, telmisartan [2] ---> SmPC of [2] of EMA

An orthostatic hypotension may be aggravated

Barbiturates, temazepam

Enhancement of the central depressive effect may occur if temazepam is combined with barbiturates

Barbiturates, testosterone undecanoate [2] ---> SmPC of [2] of eMC

Concurrent administration of liver enzyme inducing may decrease the effect of testosterone undecanoate.

Barbiturates, tetracosactide

The enzymatic induction may increase the metabolism and decrease the plasma concentrations of released glucocorticoid

Barbiturates, tetracyclic antidepressant ---> SmPC of [trazodone] of eMC

The metabolism of antidepressants is accelerated due to hepatic effects by barbiturates

Barbiturates, tetracyclines

Concurrent use of barbiturates may decrease plasma levels of tetracyclines.

Barbiturates, tetrazepam

The co-administration may mutually enhance the CNS depressant effects

Barbiturates, thalidomide [2] ---> SmPC of [2] of EMA

Thalidomide has sedative properties thus may enhance the sedative effects of other medicinal products

Barbiturates, theophylline [2] ---> SmPC of [2] of eMC

The barbiturates increase clearance of theophylline and it may be necessary to increase dosage to ensure a therapeutic effect

Barbiturates, thiazides ---> SmPC of [amlodipine/valsartan/hydrochlorothiazide] of EMA

Concomitant administration of thiazide diuretics with substances that also have a blood pressure lowering effect (e.g.by reducing sympathetic central nervous system activity or direct vasodilatation) may potentiate orthostatic hypotension.

Barbiturates, thiethylperazine

The co-administration may potentiate the CNS depressant effect

Barbiturates, thiopental

The CNS depressant can enhance the respiratory depressor effect of thiopental

Barbiturates, tiapride

Enhancement of CNS depressant effect

Barbiturates, tibolone [2] ---> SmPC of [2] of eMC

CYP3A4 inducing compounds such as barbiturates, carbamazepine, hydantoins and rifampicin may enhance the metabolism of tibolone and thus affect its therapeutic effect.

Barbiturates, timolol [2] ---> SmPC of [2] of eMC

Concomitant administration of timolol with barbiturates may increase the blood pressure lowering effect.

Barbiturates, tolvaptan [2] ---> SmPC of [2] of EMA

Tolvaptan plasma concentrations have been decreased by up to 87% (AUC) after the administration of CYP3A4 inducers. Caution should be exercised in co-administering CYP3A4 inducers with tolvaptan.

Barbiturates, tramadol [2] ---> SmPC of [2] of eMC

Concomitant administration of tramadol with other centrally acting drugs may potentiate CNS depressant effects.

Barbiturates, tranylcypromine

The MAOI may enhance the effects of barbiturate

Barbiturates, trazodone [2] ---> SmPC of [2] of eMC

The metabolism of antidepressants is accelerated due to hepatic effects by barbiturates

Barbiturates, triamcinolone acetonide

Hepatic enzyme inducers may increase the metabolic clearance of triamcinolone

Barbiturates, triamcinolone [2] ---> SmPC of [2] of eMC

Hepatic enzyme inducers may increase the metabolic clearance of triamcinolone

Barbiturates, triamterene

The combination likely enhances the hypotensive effect

Barbiturates, triamterene/hydrochlorothiazide

The antihypertensive effect of triamterene/hydrochlorothiazide may be enhanced by barbiturates

Barbiturates, tricyclic antidepressant ---> SmPC of [trazodone] of eMC

The metabolism of antidepressants is accelerated due to hepatic effects by barbiturates

Barbiturates, triiodthyronine

The enzymatic induction may decrease the plasma levels and the effect of liothyronine.

Barbiturates, trimethoprim

Trimethoprim may induce folate deficiency in patients predisposed to folate deficiency such as those receiving concomitant folate antagonists or anticonvulsants.

Barbiturates, trimethoprim/sulfamethoxazol

The administration of barbiturates increases toxicity of cotrimoxazole

Barbiturates, trimipramine [2] ---> SmPC of [2] of eMC

The co-administration of trimipramine with other CNS depressants may increase the CNS depressant effect. Barbiturates may increase the rate of metabolism.

Barbiturates, urapidil

Urapidil at large doses may prolong the effect duration of barbiturates

Barbiturates, vitamin D ---> SmPC of [cholecalciferol] of eMC

The co-administration may increase the metabolism and decrease the effect of vitamin D3

Barbiturates, warfarin [2] ---> SmPC of [2] of eMC

Barbiturates antagonise the effect of warfarin

Barbiturates, xipamide [2] ---> SmPC of [2] of eMC

The dosage of other hypotensive drugs may require adjustment when used in conjunction with xipamide

Barbiturates, zofenopril

Postural hypotension may occur

Barbiturates, zotepine

The combination may enhance the respiratory depressant effect of barbiturate. The barbiturate, enzymatic inductor, may decrease the plasma levels of zotepine

Barbiturates, zuclopenthixol [2] ---> SmPC of [2] of eMC

Zuclopenthixol enhances the effects of barbiturates