Tolbutamide Interactions

No significant interactions with digoxin, hydrochlorothiazide, hydralazine, sulfinpyrazone, oral contraceptives, tolbutamide, or warfarin have been observed.

Source: FDA drug label - acebutolol hydrochloride

Tolbutamide's conversion to inactive metabolites has been shown to be catalyzed by xanthine oxidase from rat liver.

Source: FDA drug label - allopurinol

DRUG-DRUG INTERACTIONS Patients who are applying bexarotene gel should not concurrently use products that contain DEET ( N,N -diethyl- m -toluamide), a common component of insect repellent products.

Source: FDA drug label - bexarotene

Therapeutic levels of aspirin, desipramine, diazepam, flurazepam, ibuprofen, propranolol, thioridazine, and tolbutamide had only a limited effect on the extent of binding of buspirone to plasma proteins (see CLINICAL PHARMACOLOGY ).

Source: FDA drug label - buspirone

Therapeutic levels of aspirin, desipramine, diazepam, flurazepam, ibuprofen, propranolol, thioridazine, and tolbutamide had only a limited effect on the extent of binding of buspirone to plasma proteins (see CLINICAL PHARMACOLOGY ).

Source: FDA drug label - buspirone hydrochloride

No depressant effect on blood levels in humans was noted when colestipol hydrochloride was administered with any of the following drugs: aspirin, clindamycin, clofibrate, methyldopa, nicotinic acid (niacin), tolbutamide, phenytoin or warfarin.

Source: FDA drug label - colestipol hydrochloride

Binding to plasma proteins is reduced by warfarin and clofibrate and increased by tolbutamide.

Source: FDA drug label - dantrolene

Binding to plasma proteins is reduced by warfarin and clofibrate and increased by tolbutamide.

Source: FDA drug label - dantrolene sodium

Since desogestrel is mainly metabolized by the cytochrome P450 2C9 enzyme (CYP 2C9) to form etonogestrel, the active progestin, there is a possibility of interaction with CYP 2C9 substrates or inhibitors (such as: ibuprofen, piroxicam, naproxen, phenytoin, fluconazole, diclofenac, tolbutamide, glipizide, celecoxib, sulfamethoxazole, isoniazid, torsemide, irbesartan, losartan, and valsartan).

Source: FDA drug label - desogestrel and ethinyl estradiol

Tolbutamide In diabetic patients receiving diflunisal and tolbutamide, no significant effects were seen on tolbutamide plasma levels or fasting blood glucose.

Source: FDA drug label - diflunisal

Tolbutamide From in vitro experiments, the unbound fraction of tolbutamide was increased from 20% to 50% when added to plasma samples taken from patients treated with valproate.

Source: FDA drug label - divalproex sodium

Tolbutamide: From in vitro experiments, the unbound fraction of tolbutamide was increased from 20% to 50% when added to plasma samples taken from patients treated with valproate.

Source: FDA drug label - divalproex sodium er

(See CONTRAINDICATIONS and PRECAUTIONS .) Oral hypoglycemics: The effects of fluconazole on the pharmacokinetics of the sulfonylurea oral hypoglycemic agents tolbutamide, glipizide, and glyburide were evaluated in three placebo-controlled studies in normal volunteers. (See PRECAUTIONS .) Tolbutamide: In 13 normal male volunteers, there was significant increase in tolbutamide (500 mg single dose) AUC and C max following the administration of fluconazole. There was a mean ± SD increase in tolbutamide AUC of 26% ± 9% (range: 12 to 39%).

Source: FDA drug label - fluconazole

Drugs That Affect Phenytoin Concentrations Interacting Agent Examples Drugs that may increase phenytoin serum levels Antiepileptic drugs Ethosuximide, felbamate, oxcarbazepine, methsuximide, topiramate Azoles Fluconazole, ketoconazole, itraconazole, miconazole, voriconazole Antineoplastic agents Capecitabine, fluorouracil Antidepressants Fluoxetine, fluvoxamine, sertraline Gastric acid reducing agents H 2 antagonists (cimetidine), omeprazole Sulfonamides Sulfamethizole, sulfaphenazole, sulfadiazine, sulfamethoxazole-trimethoprim Other Acute alcohol intake, amiodarone, chloramphenicol, chlordiazepoxide, disulfiram, estrogen, fluvastatin, isoniazid, methylphenidate, phenothiazines, salicylates, ticlopidine, tolbutamide, trazodone, warfarin Drugs that may decrease phenytoin serum levels Antineoplastic agents usually in combination Bleomycin, carboplatin, cisplatin, doxorubicin, methotrexate Antiviral agents Fosamprenavir, nelfinavir, ritonavir Antiepileptic drugs Carbamazepine, vigabatrin Other Chronic alcohol abuse, diazepam, diazoxide, folic acid, reserpine, rifampin, St.

Source: FDA drug label - fosphenytoin sodium

7.5 Drugs with No Observed Clinically Significant Interactions with MAVYRET No dose adjustment is required when MAVYRET is coadministered with the following medications: abacavir, amlodipine, caffeine, dextromethorphan, dolutegravir, elvitegravir/ cobicistat, emtricitabine, ethinyl estradiol of 20 mcg or less, felodipine, lamivudine, lamotrigine, losartan, midazolam, norethindrone or other progestin-only contraceptives, omeprazole, raltegravir, rilpivirine, sofosbuvir, tacrolimus, tenofovir alafenamide, tenofovir disoproxil fumarate, tolbutamide, and valsartan.

Source: FDA drug label - glecaprevir and pibrentasvir

In vitro binding studies with human serum proteins indicate that glipizide binds differently than tolbutamide and does not interact with salicylate or dicumarol.

Source: FDA drug label - glipizide

In vitro binding studies with human serum proteins indicate that glipizide binds differently than tolbutamide and does not interact with salicylate or dicumarol.

Source: FDA drug label - glipizide and metformin hydrochloride

In vitro studies show significant inhibition of the formation of oxidized irbesartan metabolites with the known cytochrome CYP 2C9 substrates/inhibitors sulphenazole, tolbutamide and nifedipine.

Source: FDA drug label - irbesartan

Therapeutic concentrations of digoxin , warfarin , ibuprofen , naproxen , piroxicam , acetaminophen , phenytoin and tolbutamide did not alter ketorolac tromethamine protein binding.

Source: FDA drug label - ketorolac tromethamine

Drugs that alter thyroid hormone secretion Drugs that may decrease thyroid hormone secretion, which may result in hypothyroidism Aminoglutethimide Amiodarone Iodide (including iodine-containing Radiographic contrast agents) Lithium Methimazole Propylthioracil (PTU) Sulfonamides Tolbutamide Long-term lithium therapy can result in goiter in up to 50% of patients, and either subclinical or overt hypothyroidism, each in up to 20% of patients.

Source: FDA drug label - levothyroxine sodium

Table 2: Clinically Relevant Interactions Affecting Co-Administered Drugs Sensitive CYP2C9 Substrates (e.g., celecoxib, tolbutamide) or CYP2C9 Substrates with a Narrow Therapeutic Index (e.g., phenytoin, warfarin) Clinical Impact Increased exposure of the co-administered drugs metabolized by CYP2C9.

Source: FDA drug label - nitisinone

Table 2: Drugs That Affect Phenytoin Concentrations Interacting Agent Examples Drugs that may increase phenytoin serum levels Antiepileptic drugs Ethosuximide, felbamate, oxcarbazepine, methsuximide, topiramate Azoles Fluconazole, ketoconazole, itraconazole, miconazole, voriconazole Antineoplastic agents Capecitabine, fluorouracil Antidepressants Fluoxetine, fluvoxamine, sertraline Gastric acid reducing agents H 2 antagonists (cimetidine), omeprazole Sulfonamides Sulfamethizole, sulfaphenazole, sulfadiazine, sulfamethoxazole-trimethoprim Other Acute alcohol intake, amiodarone, chloramphenicol, chlordiazepoxide, disulfiram, estrogen, fluvastatin, isoniazid, methylphenidate, phenothiazines, salicylates, ticlopidine, tolbutamide, trazodone, warfarin Drugs that may decrease phenytoin serum levels Antacids Antacids may affect absorption of phenytoin.

Source: FDA drug label - phenytoin

Table 1: Drugs That Affect Phenytoin Concentrations Interacting Agent Examples Drugs that may increase phenytoin serum levels Antiepileptic drugs Ethosuximide, felbamate, oxcarbazepine, methsuximide, topiramate Azoles Fluconazole, ketoconazole, itraconazole, miconazole, voriconazole Antineoplastic agents Capecitabine, fluorouracil Antidepressants Fluoxetine, fluvoxamine, sertraline Gastric acid reducing agents H 2 antagonists (cimetidine), omeprazole Sulfonamides Sulfamethizole, sulfaphenazole, sulfadiazine, sulfamethoxazole trimethoprim Other Acute alcohol intake, amiodarone, chloramphenicol, chlordiazepoxide, disulfiram, estrogen, fluvastatin, isoniazid, methylphenidate, phenothiazines, salicylates, ticlopidine, tolbutamide, trazodone, warfarin Drugs that may decrease phenytoin serum levels Antineoplastic agents usually in combination Bleomycin, carboplatin, cisplatin, doxorubicin, methotrexate Antiviral agents Fosamprenavir, nelfinavir, ritonavir Antiepileptic drugs Carbamazepine, vigabatrin Other Chronic alcohol abuse, diazepam, diazoxide, folic acid, reserpine, rifampin, St.

Source: FDA drug label - phenytoin sodium

Drug Interactions Prazosin hydrochloride has been administered without any adverse drug interaction in limited clinical experience to date with the following: (1) cardiac glycosides– digitalis and digoxin; (2) hypoglycemics–insulin, chlorpropamide, phenformin, tolazamide, and tolbutamide; (3) tranquilizers and sedatives–chlordiazepoxide, diazepam, and phenobarbital; (4) antigout– allopurinol, colchicine, and probenecid; (5) antiarrhythmics–procainamide, propranolol (see WARNINGS however), and quinidine; and (6) analgesics, antipyretics and anti-inflammatories– propoxyphene, aspirin, indomethacin, and phenylbutazone.

Source: FDA drug label - prazosin

Drug Interactions Prazosin hydrochloride has been administered without any adverse drug interaction in limited clinical experience to date with the following: (1) cardiac glycosides– digitalis and digoxin; (2) hypoglycemics–insulin, chlorpropamide, phenformin, tolazamide, and tolbutamide; (3) tranquilizers and sedatives–chlordiazepoxide, diazepam, and phenobarbital; (4) antigout– allopurinol, colchicine, and probenecid; (5) antiarrhythmics–procainamide, propranolol ( see WARNINGS however), and quinidine; and (6) analgesics, antipyretics and anti-inflammatories– propoxyphene, aspirin, indomethacin, and phenylbutazone.

Source: FDA drug label - prazosin hydrochloride

Substrates or Inhibitors of CYP2C19 Blood levels and/or toxicity of propranolol may be increased by co-administration with substrates or inhibitors of CYP2C19, such as fluconazole, cimetidine, fluoxetine, fluvoxamine, teniposide, and tolbutamide. Substrates or Inhibitors of CYP2C19 Blood levels and/or toxicity of propranolol may be increased by co-administration with substrates or inhibitors of CYP2C19, such as fluconazole, cimetidine, fluoxetine, fluvoxamine, teniposide, and tolbutamide.

Source: FDA drug label - propranolol hydrochloride

Due to the competition of salicylate with other drugs for binding to serum albumin the following drug interactions may occur: Drug Description of Interaction Tolbutamide; Sulfonylureas Hypoglycemia potentiated Methotrexate Decrease tubular reabsorption; clinical toxicity from methotrexate can result Oral Anticoagulants Increased bleeding II.

Source: FDA drug label - salicylic acid

Due to the competition of salicylate with other drugs for binding to serum albumin the following drug interactions may occur: Drug Description of Interaction Tolbutamide; Sulfonylureas Hypoglycemia potentiated Methotrexate Decreases tubular reabsorption; clinical toxicity from methotrexate can result Oral Anticoagulants Increased bleeding B.

Source: FDA drug label - salicylic acid 10%

Additionally, no dosage adjustment is required for diazepam, lithium, atenolol, tolbutamide, digoxin, and drugs metabolized by CYP3A4, when sertraline hydrochloride is administered concomitantly [ See Clinical Pharmacology ( 12.3 ) ].

Source: FDA drug label - sertraline

Hypoglycemic Drugs –In a placebo-controlled trial in normal volunteers, administration of sertraline hydrochloride for 22 days (including 200 mg/day for the final 13 days) caused a statistically significant 16% decrease from baseline in the clearance of tolbutamide following an intravenous 1000 mg dose. Sertraline hydrochloride administration did not noticeably change either the plasma protein binding or the apparent volume of distribution of tolbutamide, suggesting that the decreased clearance was due to a change in the metabolism of the drug. The clinical significance of this decrease in tolbutamide clearance is unknown.

Source: FDA drug label - sertraline hydrochloride

In vitro studies with human liver microsomes showed that terbinafine does not inhibit the metabolism of tolbutamide, ethinylestradiol, ethoxycoumarin, cyclosporine, cisapride and fluvastatin.

Source: FDA drug label - terbinafine

In vitro studies with human liver microsomes showed that terbinafine does not inhibit the metabolism of tolbutamide, ethinylestradiol, ethoxycoumarin, cyclosporine, cisapride and fluvastatin.

Source: FDA drug label - terbinafine hydrochloride

In vitro studies with human liver microsomes showed that terbinafine does not inhibit the metabolism of tolbutamide, ethinylestradiol, ethoxycoumarin, cyclosporine, cisapride and fluvastatin.

Source: FDA drug label - terbinafine tablets 250 mg

Glimepiride Glipizide Glyburide Pioglitazone Repaglinide Tolbutamide ↔ Glimepiride (CYP2C9) ↔ Glipizide (CYP2C9) ↔ Glyburide (CYP2C9) ↕ Pioglitazone (CYP2C8 and CYP3A4) ↕ Repaglinide (CYP2C8 and CYP3A4) ↔ Tolbutamide (CYP2C9) The effect of TPV/ritonavir on CYP2C8 substrate is not known.

Source: FDA drug label - tipranavir

The experiments included warfarin (0.5 to 7.2 mcg/mL), phenytoin (4.0 to 38.7 mcg/mL), tolbutamide (24.5 to 96.1 mcg/mL) and digitoxin (9.0 to 27.0 mcg/mL). Due to its affinity to cytochrome P450 2C9 in vitro, tolcapone may interfere with drugs, whose clearance is dependent on this metabolic pathway, such as tolbutamide and warfarin. However, in an in vivo interaction study, tolcapone did not change the pharmacokinetics of tolbutamide.

Source: FDA drug label - tolcapone

7.6 Effect of Toremifene on CYP2C9 Substrates In a study of 20 healthy subjects, 500 mg tolbutamide once daily (days 7 and 19) coadministered with toremifene as a 480 mg loading dose followed by 80 mg once daily for 16 days. Following coadministration on days 7 and 19 plasma tolbutamide Cmax and AUC were increased by less than 30%. A reduction of similar magnitude was observed for hydroxytolbutamide and carboxytolbutamide Cmax and AUC.

Source: FDA drug label - toremifene citrate

Tolbutamide From in vitro experiments, the unbound fraction of tolbutamide was increased from 20% to 50% when added to plasma samples taken from patients treated with valproate.

Source: FDA drug label - valproate sodium

Tolbutamide From in vitro experiments, the unbound fraction of tolbutamide was increased from 20% to 50% when added to plasma samples taken from patients treated with valproate.

Source: FDA drug label - valproic acid

In vivo , venlafaxine 75 mg by mouth every 12 hours did not alter the pharmacokinetics of a single 500 mg dose of tolbutamide or the CYP2C9 mediated formation of 4-hydroxy-tolbutamide.

Source: FDA drug label - venlafaxine

In vivo , venlafaxine 75 mg by mouth every 12 hours did not alter the pharmacokinetics of a single 500 mg dose of tolbutamide or the CYP2C9 mediated formation of 4-hydroxy-tolbutamide.

Source: FDA drug label - venlafaxine hydrochloride, extended release

In vivo , venlafaxine 75 mg by mouth every 12 hours did not alter the pharmacokinetics of a single 500 mg dose of tolbutamide or the CYP2C9 mediated formation of 4-hydroxy-tolbutamide.

Source: FDA drug label - venlafaxine hydrochloride

No formal drug-drug interaction studies with zafirlukast and other drugs known to be metabolized by the cytochrome P450 2C9 isoenzyme (eg, tolbutamide, phenytoin, carbamazepine) have been conducted; however, care should be exercised when zafirlukast is coadministered with these drugs.

Source: FDA drug label - zafirlukast