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Famotidine, Calcium Carbonate, and Magnesium Hydroxide

Generic name: calcium carbonate/famotidine/magnesium hydroxide systemic

Brand names: Pepcid Complete, Dual Action Complete, Tums Dual Action, Acid Controller Complete Dual Action, Complete Acid Reducer plus Antacid, Dual-Action Acid Controller Complete, Acid Controller Complete, Acid Reducer Plus Antacid, Duo Fusion

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Tablet, chewable, oral:

Dual Action Complete: Famotidine 10 mg, calcium carbonate 800 mg, and magnesium hydroxide 165 mg [contains calcium 320 mg/tablet, magnesium 70 mg/tablet, phenylalanine 2.2 mg/tablet; berry flavor] [DSC]

Pepcid Complete: Famotidine 10 mg, calcium carbonate 800 mg, and magnesium hydroxide 165 mg [contains calcium 320 mg/tablet, magnesium 70 mg/tablet; berry flavor]

Pepcid Complete: Famotidine 10 mg, calcium carbonate 800 mg, and magnesium hydroxide 165 mg [contains calcium 320 mg/tablet, magnesium 70 mg/tablet; mint flavor]

Pepcid Complete: Famotidine 10 mg, calcium carbonate 800 mg, and magnesium hydroxide 165 mg [contains calcium 320 mg/tablet, magnesium 70 mg/tablet, tartrazine; tropical fruit flavor]

Generic: Famotidine 10 mg, calcium carbonate 800 mg, and magnesium hydroxide 165

Pharmacology

Mechanism of Action

See individual agents.

Use: Labeled Indications

Heartburn: Relief of heartburn due to acid indigestion and sour stomach

Contraindications

OTC labeling: When used for self-medication, do not use if you are allergic to famotidine or other acid reducers; trouble or pain swallowing food; vomiting with blood; bloody or black stools; concomitant use with other acid reducers.

Dosage and Administration

Dosing: Adult

Note: Each tablet contains famotidine 10 mg, calcium carbonate 800 mg, and magnesium hydroxide 165 mg.

Heartburn: Oral: One tablet to relieve symptoms; maximum: 2 tablets in 24 hours

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Children ≥12 years and adolescents: Refer to adult dosing.

Administration

Tablets should NOT be swallowed whole; must be chewed completely prior to swallowing.

Dietary Considerations

Some products may contain phenylalanine.

Storage

Protect from moisture.

Pepcid Complete: Store between 20°C and 25°C (68°F and 77°F).

Drug Interactions

Acalabrutinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Acalabrutinib. Management: To minimize the potential for a significant interaction, separate administration of these agents by giving acalabrutinib 2 hours before ingestion of a histamine-2 receptor antagonist. Consider therapy modification

Acalabrutinib: Antacids may decrease the serum concentration of Acalabrutinib. Management: Separate administration of acalabrutinib from the administration of any antacids by at least 2 hours in order to minimize the potential for a significant interaction. Consider therapy modification

Alfacalcidol: May increase the serum concentration of Magnesium Salts. Consider therapy modification

Allopurinol: Antacids may decrease the absorption of Allopurinol. Consider therapy modification

Alpha-Lipoic Acid: Magnesium Salts may decrease the absorption of Alpha-Lipoic Acid. Alpha-Lipoic Acid may decrease the absorption of Magnesium Salts. Consider therapy modification

Alpha-Lipoic Acid: Calcium Salts may decrease the absorption of Alpha-Lipoic Acid. Alpha-Lipoic Acid may decrease the absorption of Calcium Salts. Consider therapy modification

Amphetamines: Antacids may decrease the excretion of Amphetamines. Monitor therapy

Antipsychotic Agents (Phenothiazines): Antacids may decrease the absorption of Antipsychotic Agents (Phenothiazines). Monitor therapy

Atazanavir: Antacids may decrease the absorption of Atazanavir. Consider therapy modification

Atazanavir: Histamine H2 Receptor Antagonists may decrease the serum concentration of Atazanavir. Management: Specific dose limitations and administration guidelines exist; consult full interaction monograph or atazanavir prescribing information. Consider therapy modification

Baloxavir Marboxil: Polyvalent Cation Containing Products may decrease the serum concentration of Baloxavir Marboxil. Avoid combination

Bictegravir: Calcium Salts may decrease the serum concentration of Bictegravir. Management: Bictegravir, emtricitabine, and tenofovir alafenamide can be administered with calcium salts under fed conditions, but coadministration with or 2 hours after a calcium salt is not recommended under fasting conditions. Consider therapy modification

Bictegravir: Polyvalent Cation Containing Products may decrease the serum concentration of Bictegravir. Management: Administer bictegravir under fasting conditions at least 2 hours before or 6 hours after polyvalent cation containing products. Coadministration of bictegravir with or 2 hours after most polyvalent cation products is not recommended. Consider therapy modification

Bisacodyl: Antacids may diminish the therapeutic effect of Bisacodyl. Antacids may cause the delayed-release bisacodyl tablets to release drug prior to reaching the large intestine. Gastric irritation and/or cramps may occur. Consider therapy modification

Bismuth Subcitrate: Antacids may diminish the therapeutic effect of Bismuth Subcitrate. Management: Avoid administration of antacids within 30 minutes of bismuth subcitrate (tripotassium bismuth dicitrate) administration. Consider therapy modification

Bisphosphonate Derivatives: Polyvalent Cation Containing Products may decrease the serum concentration of Bisphosphonate Derivatives. Management: Avoid administration of oral medications containing polyvalent cations within: 2 hours before or after tiludronate/clodronate/etidronate; 60 minutes after oral ibandronate; or 30 minutes after alendronate/risedronate. Exceptions: Pamidronate; Zoledronic Acid. Consider therapy modification

Bosutinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Bosutinib. Management: Administer histamine H2 receptor antagonists more than 2 hours before or after bosutinib. Consider therapy modification

Bosutinib: Antacids may decrease the serum concentration of Bosutinib. Management: Administer antacids more than 2 hours before or after bosutinib. Consider therapy modification

Bromperidol: Antacids may decrease the absorption of Bromperidol. Monitor therapy

Calcitriol (Systemic): May increase the serum concentration of Magnesium Salts. Management: Consider using a non-magnesium-containing antacid or phosphate-binding product in patients also receiving calcitriol. If magnesium-containing products must be used with calcitriol, serum magnesium concentrations should be monitored closely. Consider therapy modification

Calcium Acetate: Calcium Salts may enhance the adverse/toxic effect of Calcium Acetate. Avoid combination

Calcium Channel Blockers: Calcium Salts may diminish the therapeutic effect of Calcium Channel Blockers. Monitor therapy

Calcium Channel Blockers: May enhance the adverse/toxic effect of Magnesium Salts. Magnesium Salts may enhance the hypotensive effect of Calcium Channel Blockers. Monitor therapy

Calcium Polystyrene Sulfonate: Laxatives (Magnesium Containing) may enhance the adverse/toxic effect of Calcium Polystyrene Sulfonate. More specifically, concomitant use of calcium polystyrene sulfonate with magnesium-containing laxatives may result in metabolic alkalosis or with sorbitol may result in intestinal necrosis. Management: Avoid concomitant use of calcium polystyrene sulfonate (rectal or oral) and magnesium-containing laxatives. Avoid combination

Captopril: Antacids may decrease the serum concentration of Captopril. Monitor therapy

Cardiac Glycosides: Calcium Salts may enhance the arrhythmogenic effect of Cardiac Glycosides. Monitor therapy

Cefditoren: Histamine H2 Receptor Antagonists may decrease the serum concentration of Cefditoren. Management: Concomitant use of cefditoren with H2-antagonists and antacids is not recommended. Consider alternative methods to control acid reflux (eg, diet modification) or alternative antimicrobial therapy if use of H2-antagonists can not be avoided. Consider therapy modification

Cefditoren: Antacids may decrease the serum concentration of Cefditoren. Management: Concomitant use of cefditoren with antacids is not recommended. Consider alternative methods to control acid reflux (eg, diet modification) or alternative antimicrobial therapy. If antacid therapy can not be avoided, separate dosing by several hours. Consider therapy modification

Cefpodoxime: Histamine H2 Receptor Antagonists may decrease the absorption of Cefpodoxime. Separate oral doses by at least 2 hours. Monitor therapy

Cefpodoxime: Antacids may decrease the serum concentration of Cefpodoxime. Monitor therapy

Cefuroxime: Histamine H2 Receptor Antagonists may decrease the absorption of Cefuroxime. Separate oral doses by at least 2 hours. Avoid combination

Chloroquine: Antacids may decrease the serum concentration of Chloroquine. Management: Separate administration of antacids and chloroquine by at least 4 hours to minimize any potential negative impact of antacids on chloroquine bioavailability. Consider therapy modification

Corticosteroids (Oral): Antacids may decrease the bioavailability of Corticosteroids (Oral). Management: Consider separating doses by 2 or more hours. Budesonide enteric coated tablets could dissolve prematurely if given with drugs that lower gastric acid, with unknown impact on budesonide therapeutic effects. Consider therapy modification

Cysteamine (Systemic): Histamine H2 Receptor Antagonists may diminish the therapeutic effect of Cysteamine (Systemic). Monitor therapy

Cysteamine (Systemic): Antacids may diminish the therapeutic effect of Cysteamine (Systemic). Monitor therapy

Dabigatran Etexilate: Antacids may decrease the serum concentration of Dabigatran Etexilate. Management: Dabigatran etexilate Canadian product labeling recommends avoiding concomitant use with antacids for 24 hours after surgery. In other situations, administer dabigatran etexilate 2 hours prior to antacids. Monitor clinical response to dabigatran therapy. Consider therapy modification

Dacomitinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Dacomitinib. Management: Administer dacomitinib at least 6 hours before or 10 hours after an histamine H2-receptor antagonist (H2RA). Consider therapy modification

Dasatinib: Histamine H2 Receptor Antagonists may decrease the absorption of Dasatinib. Management: Antacids (taken 2 hours before or after dasatinib administration) can be used in place of H2-antagonists if some acid-reducing therapy is needed. Avoid combination

Deferiprone: Polyvalent Cation Containing Products may decrease the serum concentration of Deferiprone. Management: Separate administration of deferiprone and oral medications or supplements that contain polyvalent cations by at least 4 hours. Consider therapy modification

Delavirdine: Histamine H2 Receptor Antagonists may decrease the serum concentration of Delavirdine. Management: Chronic therapy with H2-antagonists should be avoided in patients who are being treated with delavirdine. The clinical significance of short-term H2-antagonist therapy with delavirdine is uncertain, but such therapy should be undertaken with caution. Avoid combination

Dexmethylphenidate: Antacids may increase the absorption of Dexmethylphenidate. Specifically, antacids may interfere with the normal release of drug from the extended-release capsules (Focalin XR brand), which could result in both increased absorption (early) and decreased delayed absorption. Monitor therapy

Dexmethylphenidate: Histamine H2 Receptor Antagonists may increase the absorption of Dexmethylphenidate. Specifically, H2-antagonists may interfere with the normal release of drug from the extended-release capsules (Focalin XR brand), which could result in both increased absorption (early) and decreased delayed absorption. Monitor therapy

Diacerein: Antacids may decrease the absorption of Diacerein. Monitor therapy

Dichlorphenamide: May increase the serum concentration of Famotidine. Avoid combination

DOBUTamine: Calcium Salts may diminish the therapeutic effect of DOBUTamine. Monitor therapy

Dolutegravir: Calcium Salts may decrease the serum concentration of Dolutegravir. Management: Administer dolutegravir at least 2 hours before or 6 hours after oral calcium. Administer dolutegravir/rilpivirine at least 4 hours before or 6 hours after oral calcium salts. Alternatively, dolutegravir and oral calcium can be taken together with food. Consider therapy modification

Dolutegravir: Magnesium Salts may decrease the serum concentration of Dolutegravir. Management: Administer dolutegravir at least 2 hours before or 6 hours after oral magnesium salts. Administer the dolutegravir/rilpivirine combination product at least 4 hours before or 6 hours after oral magnesium salts. Consider therapy modification

Doxercalciferol: May enhance the hypermagnesemic effect of Magnesium Salts. Management: Consider using a non-magnesium-containing antacid or phosphate-binding product in patients also receiving doxercalciferol. If magnesium-containing products must be used with doxercalciferol, serum magnesium concentrations should be monitored closely. Consider therapy modification

Eltrombopag: Polyvalent Cation Containing Products may decrease the serum concentration of Eltrombopag. Management: Administer eltrombopag at least 2 hours before or 4 hours after oral administration of any polyvalent cation containing product. Consider therapy modification

Elvitegravir: Antacids may decrease the serum concentration of Elvitegravir. Management: Separate administration of antacids and elvitegravir-containing products by at least 2 hours in order to minimize the risk for an interaction. Consider therapy modification

Erdafitinib: Serum Phosphate Level-Altering Agents may diminish the therapeutic effect of Erdafitinib. Management: Avoid coadministration of serum phosphate level-altering agents with erdafitinib before initial dose increase period based on serum phosphate levels (Days 14 to 21). Consider therapy modification

Erlotinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Erlotinib. Management: Avoid H2-antagonists in patients receiving erlotinib when possible. If concomitant treatment cannot be avoided, erlotinib should be dosed once daily, 10 hours after and at least 2 hours before H2-antagonist dosing. Consider therapy modification

Erlotinib: Antacids may decrease the serum concentration of Erlotinib. Management: Separate the administration of erlotinib and any antacid by several hours in order to minimize the risk of a significant interaction. Consider therapy modification

Estramustine: Calcium Salts may decrease the absorption of Estramustine. Consider therapy modification

Fexofenadine: Antacids may decrease the serum concentration of Fexofenadine. Management: Separate the administration of fexofenadine and aluminum- or magnesium-containing antacids. Consider therapy modification

Fosamprenavir: Histamine H2 Receptor Antagonists may decrease the serum concentration of Fosamprenavir. Cimetidine may also inhibit the metabolism of the active metabolite amprenavir, making its effects on fosamprenavir/amprenavir concentrations difficult to predict. Monitor therapy

Fosinopril: Antacids may decrease the serum concentration of Fosinopril. Management: The US and Canadian fosinopril manufacturer labels recommend separating the doses of antacids and fosinopril by 2 hours. Consider therapy modification

Gabapentin: Magnesium Salts may enhance the CNS depressant effect of Gabapentin. Specifically, high dose intravenous/epidural magnesium sulfate may enhance the CNS depressant effects of gabapentin. Magnesium Salts may decrease the serum concentration of Gabapentin. Management: Administer gabapentin at least 2 hours after use of a magnesium-containing antacid. Monitor patients closely for evidence of reduced response to gabapentin therapy. Monitor for CNS depression if high dose IV/epidural magnesium sulfate is used. Consider therapy modification

Gefitinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Gefitinib. Management: Administer gefitinib at least 6 hours before or after administration of a histamine H2-antagonist, and closely monitor clinical response to gefitinib. Consider therapy modification

Gefitinib: Antacids may decrease the serum concentration of Gefitinib. Management: Administer gefitinib at least 6 hours before or after administration of an antacid, and closely monitor clinical response to gefitinib. Consider therapy modification

Hyoscyamine: Antacids may decrease the serum concentration of Hyoscyamine. Management: Administer immediate release hyoscyamine before meals and antacids after meals when these agents are given in combination. Consider therapy modification

Indinavir: Histamine H2 Receptor Antagonists may decrease the serum concentration of Indinavir. Monitor therapy

Iron Preparations: Antacids may decrease the absorption of Iron Preparations. Management: Separate dosing of oral iron preparations and antacids as much as possible to avoid decreased efficacy of iron preparation. If coadministered with antacids, monitor for decreased therapeutic effects of iron preparations. Exceptions: Ferric Carboxymaltose; Ferric Citrate; Ferric Derisomaltose; Ferric Gluconate; Ferric Hydroxide Polymaltose Complex; Ferric Pyrophosphate Citrate; Ferumoxytol; Iron Dextran Complex; Iron Sucrose. Consider therapy modification

Itraconazole: Antacids may decrease the serum concentration of Itraconazole. Antacids may increase the serum concentration of Itraconazole. Management: Administer Sporanox brand itraconazole at least 2 hours before or 2 hours after administration of any antacids. Exposure to Tolsura brand itraconazole may be increased by antacids; consider itraconazole dose reduction. Consider therapy modification

Itraconazole: Histamine H2 Receptor Antagonists may increase the serum concentration of Itraconazole. Histamine H2 Receptor Antagonists may decrease the serum concentration of Itraconazole. Management: Administer Sporanox brand itraconazole at least 2 hours before or 2 hours after administration of any histamine H2 receptor antagonists (H2RAs). Exposure to Tolsura brand itraconazole may be increased by H2RAs; consider itraconazole dose reduction. Consider therapy modification

Ketoconazole (Systemic): Antacids may decrease the serum concentration of Ketoconazole (Systemic). Management: Administer oral ketoconazole at least 2 hours prior to use of any antacid product. Monitor patients closely for signs of inadequate clinical response to ketoconazole. Consider therapy modification

Ketoconazole (Systemic): Histamine H2 Receptor Antagonists may decrease the serum concentration of Ketoconazole (Systemic). Management: Administer oral ketoconazole at least 2 hours prior to use of any H2-receptor antagonist. Monitor patients closely for signs of inadequate clinical response to ketoconazole. Consider therapy modification

Lanthanum: Antacids may diminish the therapeutic effect of Lanthanum. Consider therapy modification

Ledipasvir: Antacids may decrease the serum concentration of Ledipasvir. Management: Separate the administration of ledipasvir and antacids by 4 hours. Consider therapy modification

Ledipasvir: Histamine H2 Receptor Antagonists may decrease the serum concentration of Ledipasvir. Consider therapy modification

Levothyroxine: Magnesium Salts may decrease the serum concentration of Levothyroxine. Management: Separate administration of oral levothyroxine and oral magnesium salts by at least 4 hours. Consider therapy modification

Mesalamine: Antacids may diminish the therapeutic effect of Mesalamine. Antacid-mediated increases in gastrointestinal pH may cause the premature release of mesalamine from specific sustained-release mesalamine products. Management: Avoid concurrent administration of antacids with sustained-release mesalamine products. Separating antacid and mesalamine administration, and/or using lower antacid doses may be adequate means of avoiding this interaction. Consider therapy modification

Mesalamine: Histamine H2 Receptor Antagonists may diminish the therapeutic effect of Mesalamine. Histamine H2-Antagonist-mediated increases in gastrointestinal pH may cause the premature release of mesalamine from specific sustained-release mesalamine products. Management: Consider avoiding concurrent administration of high-dose histamine H2-receptor antagonists with sustained-release mesalamine products. Consider therapy modification

Methenamine: Antacids may diminish the therapeutic effect of Methenamine. Consider therapy modification

Methylphenidate: Antacids may increase the absorption of Methylphenidate. Specifically, antacids may interfere with the normal release of drug from the extended-release capsules (Ritalin LA brand), which could result in both increased absorption (early) and decreased delayed absorption. Monitor therapy

Methylphenidate: Histamine H2 Receptor Antagonists may increase the absorption of Methylphenidate. Specifically, H2-antagonists may interfere with the normal release of drug from the extended-release capsules (Ritalin LA brand), which could result in both increased absorption (early) and decreased delayed absorption. Monitor therapy

MiSOPROStol: Antacids may enhance the adverse/toxic effect of MiSOPROStol. More specifically, concomitant use with magnesium-containing antacids may increase the risk of diarrhea. Management: Avoid concomitant use of misoprostol and magnesium-containing antacids. In patients requiring antacid therapy, employ magnesium-free preparations. Monitor for increased adverse effects (e.g., diarrhea, dehydration). Avoid combination

Multivitamins/Fluoride (with ADE): May increase the serum concentration of Calcium Salts. Calcium Salts may decrease the serum concentration of Multivitamins/Fluoride (with ADE). More specifically, calcium salts may impair the absorption of fluoride. Management: Avoid eating or drinking dairy products or consuming vitamins or supplements with calcium salts one hour before or after of the administration of fluoride. Consider therapy modification

Multivitamins/Fluoride (with ADE): Magnesium Salts may decrease the serum concentration of Multivitamins/Fluoride (with ADE). Specifically, magnesium salts may decrease fluoride absorption. Management: To avoid this potential interaction separate the administration of magnesium salts from administration of a fluoride-containing product by at least 1 hour. Consider therapy modification

Multivitamins/Minerals (with ADEK, Folate, Iron): Antacids may decrease the serum concentration of Multivitamins/Minerals (with ADEK, Folate, Iron). Specifically, antacids may decrease the absorption of orally administered iron. Management: Separate dosing of oral iron-containing multivitamin preparations and antacids by as much time as possible in order to minimize impact on therapeutic efficacy of the iron preparation. Consider therapy modification

Mycophenolate: Antacids may decrease the absorption of Mycophenolate. Management: Separate doses of mycophenolate and antacids by at least 2 hours. Monitor for reduced effects of mycophenolate if taken concomitant with antacids. Consider therapy modification

Mycophenolate: Magnesium Salts may decrease the serum concentration of Mycophenolate. Management: Separate doses of mycophenolate and oral magnesium salts. Monitor for reduced effects of mycophenolate if taken concomitant with oral magnesium salts. Consider therapy modification

Nelfinavir: Histamine H2 Receptor Antagonists may decrease the serum concentration of Nelfinavir. Concentrations of the active M8 metabolite may also be reduced. Monitor therapy

Neratinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Neratinib. Specifically, histamine H2 receptor antagonists may reduce neratinib absorption. Management: Administer neratinib at least 2 hours before or 10 hours after administration of a histamine H2 receptor antagonist to minimize the impact of this interaction. Avoid combination

Neuromuscular-Blocking Agents: Magnesium Salts may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Monitor therapy

Nilotinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Nilotinib. Management: The nilotinib dose should be given 10 hours after or 2 hours before the H2 receptor antagonist in order to minimize the risk of a significant interaction. Consider therapy modification

Nilotinib: Antacids may decrease the serum concentration of Nilotinib. Management: Separate the administration of nilotinib and any antacid by at least 2 hours whenever possible in order to minimize the risk of a significant interaction. Consider therapy modification

PAZOPanib: Histamine H2 Receptor Antagonists may decrease the serum concentration of PAZOPanib. Management: Avoid the use of histamine H2-antagonists in combination with pazopanib. Strategies to minimize the expected interaction between these agents (eg, dose separation) have not been investigated. Avoid combination

PenicillAMINE: Polyvalent Cation Containing Products may decrease the serum concentration of PenicillAMINE. Management: Separate the administration of penicillamine and oral polyvalent cation containing products by at least 1 hour. Consider therapy modification

Pexidartinib: Antacids may decrease the serum concentration of Pexidartinib. Management: Administer pexidartinib 2 hours before or after antacids. Consider therapy modification

Pexidartinib: Histamine H2 Receptor Antagonists may decrease the serum concentration of Pexidartinib. Management: Administer pexidartinib 2 hours before or 10 hours after histamine H2 receptor antagonists. Consider therapy modification

Phosphate Supplements: Antacids may decrease the absorption of Phosphate Supplements. Management: This applies only to oral phosphate administration. Separating administer of oral phosphate supplements from antacid administration by as long as possible may minimize the interaction. Exceptions: Sodium Glycerophosphate Pentahydrate. Consider therapy modification

Phosphate Supplements: Calcium Salts may decrease the absorption of Phosphate Supplements. Management: This applies only to oral phosphate and calcium administration. Administering oral phosphate supplements as far apart from the administration of an oral calcium salt as possible may be able to minimize the significance of the interaction. Exceptions: Sodium Glycerophosphate Pentahydrate. Consider therapy modification

Phosphate Supplements: Magnesium Salts may decrease the serum concentration of Phosphate Supplements. Management: Administer oral phosphate supplements as far apart from the administration of an oral magnesium salt as possible to minimize the significance of this interaction. Exceptions: Sodium Glycerophosphate Pentahydrate. Consider therapy modification

Posaconazole: Histamine H2 Receptor Antagonists may decrease the serum concentration of Posaconazole. Management: Avoid concurrent use of oral suspension with H2-antagonists whenever possible. Monitor patients closely for decreased antifungal effects if this combination is used. Delayed-release posaconazole tablets may be less likely to interact. Consider therapy modification

Potassium Phosphate: Antacids may decrease the serum concentration of Potassium Phosphate. Management: Consider separating administration of antacids and oral potassium phosphate by at least 2 hours to decrease risk of a significant interaction. Consider therapy modification

QuiNIDine: Antacids may decrease the excretion of QuiNIDine. Monitor therapy

QuiNINE: Antacids may decrease the serum concentration of QuiNINE. Avoid combination

Quinolones: Antacids may decrease the absorption of Quinolones. Of concern only with oral administration of quinolones. Management: Avoid concurrent administration of quinolones and antacids to minimize the impact of this interaction. Recommendations for optimal dose separation vary by specific quinolone. Exceptions: LevoFLOXacin (Oral Inhalation). Consider therapy modification

Quinolones: Calcium Salts may decrease the absorption of Quinolones. Of concern only with oral administration of both agents. Exceptions: LevoFLOXacin (Oral Inhalation); Moxifloxacin (Systemic). Consider therapy modification

Quinolones: Magnesium Salts may decrease the serum concentration of Quinolones. Management: Administer oral quinolones several hours before (4 h for moxi/pe/spar-, 2 h for others) or after (8 h for moxi-, 6 h for cipro/dela-, 4 h for lome/pe-, 3 h for gemi-, and 2 h for levo-, nor-, or ofloxacin or nalidixic acid) oral magnesium salts. Exceptions: LevoFLOXacin (Oral Inhalation). Consider therapy modification

Raltegravir: Magnesium Salts may decrease the serum concentration of Raltegravir. Management: Avoid the use of oral / enteral magnesium salts with raltegravir. No dose separation schedule has been established that adequately reduces the magnitude of interaction. Avoid combination

Rilpivirine: Antacids may decrease the serum concentration of Rilpivirine. Management: Administer antacids at least 2 hours before or 4 hours after rilpivirine. Administer antacids at least 6 hours before or 4 hours after the rilpivirine/dolutegravir combination product. Consider therapy modification

Rilpivirine: Histamine H2 Receptor Antagonists may decrease the serum concentration of Rilpivirine. Management: Administer histamine H2 receptor antagonists at least 12 hours before or 4 hours after rilpivirine. Consider therapy modification

Riociguat: Antacids may decrease the serum concentration of Riociguat. Management: Separate the administration of antacids and riociguat by at least 1 hour in order to minimize any potential interaction. Consider therapy modification

Risedronate: Histamine H2 Receptor Antagonists may increase the serum concentration of Risedronate. This applies specifically to delayed-release risedronate. Avoid combination

Rosuvastatin: Antacids may decrease the serum concentration of Rosuvastatin. Monitor therapy

Saquinavir: Histamine H2 Receptor Antagonists may increase the serum concentration of Saquinavir. Monitor therapy

Secretin: Histamine H2 Receptor Antagonists may diminish the diagnostic effect of Secretin. Specifically, use of H2-Antagonists may cause a hyperresponse in gastrin secretion in response to secretin stimulation testing, falsely suggesting gastrinoma. Management: Avoid concomitant use of histamine H2-antagonists (H2RAs) and secretin. Discontinue H2RAs at least 2 days prior to secretin administration. Consider therapy modification

Sodium Polystyrene Sulfonate: Laxatives (Magnesium Containing) may enhance the adverse/toxic effect of Sodium Polystyrene Sulfonate. More specifically, concomitant use of sodium polystyrene sulfonate with magnesium-containing laxatives may result in metabolic alkalosis or with sorbitol may result in intestinal necrosis. Management: Avoid concomitant use of sodium polystyrene sulfonate (rectal or oral) and magnesium-containing laxatives. Avoid combination

Sotalol: Antacids may decrease the serum concentration of Sotalol. Management: Avoid simultaneous administration of sotalol and antacids. Administer antacids 2 hours after sotalol. Consider therapy modification

Strontium Ranelate: Magnesium Hydroxide may decrease the serum concentration of Strontium Ranelate. Management: Separate administration of strontium ranelate and magnesium hydroxide by at least 2 hours whenever possible in order to minimize this interaction. Consider therapy modification

Sulpiride: Antacids may decrease the serum concentration of Sulpiride. Management: Separate administration of antacids and sulpiride by at least 2 hours in order to minimize the impact of antacids on sulpiride absorption. Consider therapy modification

Tafenoquine: May increase the serum concentration of OCT2 Substrates. Management: Avoid use of OCT2 substrates with tafenoquine, and if the combination cannot be avoided, monitor closely for evidence of toxicity of the OCT2 substrate and consider a reduced dose of the OCT2 substrate according to that substrate's labeling. Consider therapy modification

Tetracyclines: Antacids may decrease the absorption of Tetracyclines. Management: Separate administration of antacids and oral tetracycline derivatives by several hours when possible to minimize the extent of this potential interaction. Exceptions: Eravacycline. Consider therapy modification

Tetracyclines: Magnesium Salts may decrease the absorption of Tetracyclines. Only applicable to oral preparations of each agent. Exceptions: Eravacycline. Consider therapy modification

Tetracyclines: Calcium Salts may decrease the serum concentration of Tetracyclines. Management: If coadministration of oral calcium with oral tetracyclines can not be avoided, consider separating administration of each agent by several hours. Exceptions: Eravacycline. Consider therapy modification

Thiazide and Thiazide-Like Diuretics: May decrease the excretion of Calcium Salts. Continued concomitant use can also result in metabolic alkalosis. Monitor therapy

Thyroid Products: Calcium Salts may diminish the therapeutic effect of Thyroid Products. Management: Separate the doses of the thyroid product and the oral calcium supplement by at least 4 hours. Consider therapy modification

Trientine: Polyvalent Cation Containing Products may decrease the serum concentration of Trientine. Management: Avoid concomitant administration of trientine and oral products that contain polyvalent cations. If oral iron supplements are required, separate the administration by 2 hours. If other oral polyvalent cations are needed, separate administration by 1 hour. Consider therapy modification

Varenicline: Histamine H2 Receptor Antagonists may increase the serum concentration of Varenicline. Management: Monitor for increased varenicline adverse effects with concomitant use of cimetidine or other H2-antagonists, particularly in patients with severe renal impairment. International product labeling recommendations vary. Consult appropriate labeling. Monitor therapy

Velpatasvir: Antacids may decrease the serum concentration of Velpatasvir. Management: Separate administration of velpatasvir and antacids by at least 4 hours. Consider therapy modification

Vitamin D Analogs: Calcium Salts may enhance the adverse/toxic effect of Vitamin D Analogs. Monitor therapy

Adverse Reactions

See individual agents.

Warnings/Precautions

Dosage form specific issues:

  • Phenylalanine: Some products may contain phenylalanine.
  • Tartrazine: Some products may contain tartrazine.

Other warnings/precautions:

  • Self-medication (OTC use): When used for self-medication, patients should be instructed to consult their healthcare prescriber prior to using if they have had heartburn >3 months; heartburn with dizziness; heartburn or chest pain with lightheadedness or sweating; chest pain or shoulder pain with shortness of breath; frequent chest pain; chest or shoulder pain spreading to arms, neck, or shoulders; frequent wheezing associated with heartburn; unexplained weight loss; nausea or vomiting; or stomach pain. In addition, patients should contact their health care prescriber if this product is needed for >14 days or if the condition continues or worsens.

Pregnancy

Pregnancy Considerations

See individual agents.

Patient Education

  • Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
  • Patient may experience headache. Have patient report immediately to prescriber dizziness, passing out, fast heartbeat, abnormal heartbeat, or muscle weakness (HCAHPS).
  • Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

Source: Wolters Kluwer Health. Last updated January 30, 2020.