Famotidine interactions
Famotidine (Pepcid), an H2 blocker has 30 documented interactions across the FDA labels and fact sheets we index: 6 major, 14 moderate, 6 minor, and 4 where a label reports no significant interaction. Each entry below quotes the sentence behind it. This drug page is a starting point, not a verdict for your situation.
Major interactions (6)
Serious and fatal adverse reactions have been reported in low-birth weight and preterm neonates who received benzyl-alcohol-containing drugs intravenously. (Famotidine label, Warnings and precautions)
Famotidine Injection is contraindicated in patients with a history of serious hypersensitivity reactions (e.g., anaphylaxis) to famotidine or other H 2 -receptor antagonists. (Famotidine label, Contraindications)
Intervention Concomitant use of methylphenidate extended-release orally disintegrating tablets with a gastric pH modulator (i.e., a H2-blocker or a proton pump inhibitor) is not recommended. (Methylphenidate label, Drug interactions)
Famotidine Injection is contraindicated in patients with a history of serious hypersensitivity reactions (e.g., anaphylaxis) to famotidine or other H 2 -receptor antagonists. (Famotidine label, Contraindications)
Concomitant administration of Risedronate sodium delayed-release and H 2 blockers or PPIs is not recommended. (Risedronate label, Drug interactions)
Tizanidine (CYP1A2) Substrate : Potential for substantial increases in blood concentrations of tizanidine resulting in hypotension, bradycardia or excessive drowsiness; avoid concomitant use, if possible. (Famotidine label, Drug interactions)
Moderate interactions (14)
- Cannabidiol (prescription)anticonvulsantModerate
Tizanidine (CYP1A2 Substrate) Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. (Famotidine label, Drug interactions)
- CefpodoximecephalosporinModerate
Drug Interactions Antacids Concomitant administration of high doses of antacids (sodium bicarbonate and aluminum hydroxide) or H 2 blockers reduces peak plasma levels by 24% to 42% and the extent of absorption by 27% to 32%, respectively. (Cefpodoxime label, Drug interactions)
Tizanidine (CYP1A2 Substrate) Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. (Famotidine label, Drug interactions)
- Deferasiroxiron supplementModerate
Tizanidine (CYP1A2 Substrate) Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. (Famotidine label, Drug interactions)
- FluvoxamineSSRIModerate
Tizanidine (CYP1A2 Substrate) Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. (Famotidine label, Drug interactions)
…glimepiride, increasing the susceptibility to and/or intensity of hypoglycemia: oral anti-diabetic medications, pramlintide acetate, insulin, angiotensin converting enzyme (ACE) inhibitors, H 2 receptor antagonists, fibrates, propoxyphene, pentoxifylline, somatostatin analogs, anabolic steroids and androgens, cyclophosphamide, phenyramidol, guanethidine, fluconazole, sulfinpyrazone,… (Glimepiride label, Drug interactions)
…angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, propoxyphene, salicylates, somatostatin analogs (e.g., octreotide), sulfonamide antibiotics, nonsteroidal anti-inflammatory agents, chloramphenicol, probenecid, coumarins, voriconazole, H2 receptor antagonists, and quinolones. (Glipizide label, Drug interactions)
- IbandronatebisphosphonateModerate
H2 Blockers In healthy volunteers, co-administration with ranitidine resulted in a 20% increased bioavailability of ibandronate, which was not considered to be clinically relevant (see CLINICAL PHARMACOLOGY [12.3] ) . (Ibandronate label, Drug interactions)
Gastrointestinal Drugs Drugs that reduce gastric acidity e.g. acid neutralizing medicines such as aluminum hydroxide, or acid secretion suppressors such as H 2 - receptor antagonists and proton pump inhibitors (e.g., omeprazole). (Itraconazole label, Drug interactions)
Drugs that may decrease ketoconazole plasma concentrations Drugs that reduce the gastric acidity (e.g., acid neutralizing medicines such as aluminum hydroxide, or acid secretion suppressors such as H 2 -receptor antagonists and proton pump inhibitors) impair the absorption of ketoconazole from ketoconazole tablets. (Ketoconazole label, Drug interactions)
…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,… (Phenytoin label, Drug interactions)
- Sofosbuvir and velpatasvirantiviralModerate
Clinical Effect/Recommendation Acid Reducing Agents: ↓ velpatasvir Velpatasvir solubility decreases as pH increases. (Sofosbuvir and velpatasvir label, Drug interactions)
- Viloxazinenorepinephrine reuptake inhibitorModerate
Tizanidine (CYP1A2 Substrate) Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. (Famotidine label, Drug interactions)
…tigecycline, voriconazole, zafirlukast aprepitant, bosentan, carbamazepine, phenobarbital, rifampin CYP1A2 acyclovir, allopurinol, caffeine, cimetidine, ciprofloxacin, disulfiram, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, norfloxacin, oral contraceptives, phenylpropanolamine, propafenone, propranolol, terbinafine, thiabendazole, ticlopidine, verapamil,… (Warfarin label, Drug interactions)
Minor mentions (6)
Acid-reducing medicines lower stomach acid and can reduce the amount of iron absorbed from supplements and food. (NIH Office of Dietary Supplements, Iron)
- MidazolambenzodiazepineMinor
No change in choice reaction time or sedation index was detected after dosing with the H2 receptor antagonists. (Midazolam label, Drug interactions)
- MoexiprilACE inhibitorMinor
Moexipril hydrochloride has been used in clinical trials concomitantly with calcium-channel-blocking agents, diuretics, H 2 blockers, digoxin, oral hypoglycemic agents, and cholesterol-lowering agents. (Moexipril label, Drug interactions)
- Nisoldipinedihydropyridine calcium channel blockerMinor
No pharmacodynamic effects of either histamine H 2 receptor antagonist were observed. (Nisoldipine label, Drug interactions)
Effient can be administered with aspirin (75 mg to 325 mg per day), heparin, GPIIb/IIIa inhibitors, statins, digoxin, and drugs that elevate gastric pH, including proton pump inhibitors and H 2 blockers [see Clinical Pharmacology (12.3) ] . (Prasugrel label, Drug interactions)
Long-term acid-reducing therapy interferes with B12 absorption from food and can lead to deficiency. (NIH Office of Dietary Supplements, Vitamin B12)
No significant interaction reported (4)
Drugs Having No Clinically Important Interactions with ABILIFY MAINTENA Based on pharmacokinetic studies with oral aripiprazole, no dosage adjustment of ABILIFY MAINTENA is required when administered concomitantly with famotidine, valproate, lithium, lorazepam [see Clinical Pharmacology (12.3) ] . (Aripiprazole label, Drug interactions)
However, co-administration of CYMBALTA with aluminum- and magnesium-containing antacids (51 mEq) or CYMBALTA with famotidine, had no significant effect on the rate or extent of duloxetine absorption after administration of a 40 mg oral dose. (Duloxetine label, Drug interactions)
- Posaconazoleazole antifungalNo interaction
No clinically relevant effects on the pharmacokinetics of Noxafil delayed-release tablets were observed during concomitant use with antacids, H 2 -receptor antagonists and proton pump inhibitors, and metoclopramide [see Clinical Pharmacology (12.3) ] . (Posaconazole label, Drug interactions)
…nifedipine cefaclor nizatidine co-trimoxazole (trimethoprim and sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone theophylline absorption) isoflurane sucralfate isoniazid terbutaline,… (Theophylline label, Drug interactions)
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Open in the checkerNot medical advice. Severity reflects the label's wording, not your circumstances. A "major" flag can be routine under supervision and a "minor" one can matter at high doses. Ask a pharmacist.