Aluminum hydroxide and magnesium hydroxide

MEDICATION SAFETY ISSUES
Sound-alike/look-alike issues:
Maalox® may be confused with Maox®, Monodox®

U.S. BRAND NAMES — Alamag [OTC]; Rulox [OTC]

PHARMACOLOGIC CATEGORY
Antacid

DOSING: ADULTS — Dyspepsia: Oral: 5-10 mL 4-6 times/day, between meals and at bedtime; may be used every hour for severe symptoms

DOSING: ELDERLY — Refer to adult dosing.

DOSING: RENAL IMPAIRMENT — Aluminum and/or magnesium may accumulate in renal impairment.

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

Suspension: Aluminum hydroxide 225 mg and magnesium hydroxide 200 mg per 5 mL (360 mL)
Alamag, Rulox: Aluminum hydroxide 225 mg and magnesium hydroxide 200 mg per 5 mL (360 mL)

Tablet, chewable:
Alamag: Aluminum hydroxide 300 mg and magnesium hydroxide 150 mg

DOSAGE FORMS: CONCISE
Suspension: Aluminum hydroxide 225 mg and magnesium hydroxide 200 mg per 5 mL
Alamag [OTC], Rulox [OTC]: Aluminum hydroxide 225 mg and magnesium hydroxide 200 mg per 5 mL

Tablet, chewable:
Alamag [OTC]: Aluminum hydroxide 300 mg and magnesium hydroxide 150 mg

GENERIC EQUIVALENT AVAILABLE — Yes

USE — Antacid, hyperphosphatemia in renal failure

ADVERSE REACTIONS SIGNIFICANT
>10%: Gastrointestinal: Constipation, chalky taste, stomach cramps, fecal impaction

1% to 10%: Gastrointestinal: Nausea, vomiting, discoloration of feces (white speckles)

<1% (Limited to important or life-threatening): Hypomagnesemia, hypophosphatemia

DRUG INTERACTIONS
ACE Inhibitors: Antacids may decrease the serum concentration of ACE Inhibitors. Risk C: Monitor therapy

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

Alpha-/Beta-Agonists: Antacids may decrease the excretion of Alpha-/Beta-Agonists. Exceptions: Dipivefrin. Risk C: Monitor therapy

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

Anticonvulsants (Hydantoin): Antacids may decrease the serum concentration of Anticonvulsants (Hydantoin). Risk C: Monitor therapy

Antifungal Agents (Azole Derivatives, Systemic): Antacids may decrease the absorption of Antifungal Agents (Azole Derivatives, Systemic). Exceptions: Fluconazole; Miconazole; Voriconazole. Risk D: Consider therapy modification

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

Ascorbic Acid: May increase the absorption of Aluminum Hydroxide. Risk D: Consider therapy modification

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

Bisphosphonate Derivatives: Antacids may decrease the absorption of Bisphosphonate Derivatives. Antacids containing aluminum, calcium, or magnesium are of specific concern. Exceptions: Pamidronate; Zoledronic Acid. Risk D: Consider therapy modification

Bisphosphonate Derivatives: Magnesium Salts may decrease the absorption of Bisphosphonate Derivatives. Only oral magnesium salts are of concern. Exceptions: Pamidronate; Zoledronic Acid. Risk D: Consider therapy modification

Calcitriol: May increase the serum concentration of Magnesium Salts. Risk D: Consider therapy modification

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

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

Cefuroxime: Antacids may decrease the serum concentration of Cefuroxime. Risk C: Monitor therapy

Citric Acid Derivatives: May increase the absorption of Aluminum Hydroxide. Risk D: Consider therapy modification

Corticosteroids (Oral): Antacids may decrease the bioavailability of Corticosteroids (Oral). Risk D: Consider therapy modification

CycloSPORINE: Antacids may decrease the serum concentration of CycloSPORINE. Specifically when cyclosporine is administered orally. Risk C: Monitor therapy

Dabigatran Etexilate: Antacids may decrease the serum concentration of Dabigatran Etexilate. Risk C: Monitor therapy

Dasatinib: Antacids may decrease the absorption of Dasatinib. Risk D: Consider therapy modification

Deferasirox: Aluminum Hydroxide may diminish the therapeutic effect of Deferasirox. Risk D: Consider therapy modification

Delavirdine: Antacids may decrease the absorption of Delavirdine. Risk D: Consider therapy modification

Eltrombopag: Aluminum Hydroxide may decrease the serum concentration of Eltrombopag. Management: Separate administration of eltrombopag and any polyvalent cation (e.g., aluminum-containing products) by at least 4 hours. Risk D: Consider therapy modification

Eltrombopag: Magnesium Salts may decrease the serum concentration of Eltrombopag. Management: Separate administration of eltrombopag and any polyvalent cation (e.g., magnesium-containing products) by at least 4 hours. Risk D: 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. Risk D: Consider therapy modification

Ethambutol: Aluminum Hydroxide may decrease the absorption of Ethambutol. Risk D: Consider therapy modification

Fexofenadine: Antacids may decrease the serum concentration of Fexofenadine. Management: No specific recommendations concerning the time required between their administration are provided. Separate administration of each agent by as much time as possible to decrease the risk of an interaction. Risk D: Consider therapy modification

Iron Salts: Antacids may decrease the absorption of Iron Salts. Exceptions: Ferric Gluconate; Ferumoxytol; Iron Dextran Complex; Iron Sucrose. Risk D: Consider therapy modification

Isoniazid: Antacids may decrease the absorption of Isoniazid. Risk D: 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. Risk D: Consider therapy modification

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

Mycophenolate: Antacids may decrease the absorption of Mycophenolate. Risk D: Consider therapy modification

Mycophenolate: Magnesium Salts may decrease the absorption of Mycophenolate. This only applies to oral magnesium salts. Risk D: Consider therapy modification

Neuromuscular-Blocking Agents: Magnesium Salts may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Only of concern in patients with increased serum magnesium concentrations. Risk C: Monitor therapy

Penicillamine: Antacids may decrease the serum concentration of Penicillamine. Risk D: Consider therapy modification

Phosphate Supplements: Antacids may decrease the absorption of Phosphate Supplements. Risk D: Consider therapy modification

Phosphate Supplements: Magnesium Salts may decrease the absorption of Phosphate Supplements. Risk D: Consider therapy modification

Protease Inhibitors: Antacids may decrease the absorption of Protease Inhibitors. Exceptions: Darunavir. Risk C: Monitor therapy

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

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

Quinolone Antibiotics: Antacids may decrease the absorption of Quinolone Antibiotics. Of concern only with oral administration of quinolones. Risk D: Consider therapy modification

Quinolone Antibiotics: Magnesium Salts may decrease the absorption of Quinolone Antibiotics. Of concern only with oral administration of both agents. Risk D: Consider therapy modification

Sodium Polystyrene Sulfonate: May enhance the adverse/toxic effect of Antacids. The combined use of these two agents may result in metabolic alkalosis. Risk D: Consider therapy modification

Tetracycline Derivatives: Antacids may decrease the absorption of Tetracycline Derivatives. Risk D: Consider therapy modification

Tetracycline Derivatives: Magnesium Salts may decrease the absorption of Tetracycline Derivatives. Only applicable to oral preparations of each agent. Risk D: Consider therapy modification

Tocainide: Antacids may increase the serum concentration of Tocainide. Risk C: Monitor therapy

Trientine: Antacids may decrease the absorption of Trientine. Risk D: Consider therapy modification

Trientine: May decrease the serum concentration of Magnesium Salts. Magnesium Salts may decrease the serum concentration of Trientine. Risk D: Consider therapy modification

PREGNANCY RISK FACTOR — C (show table)

DIETARY CONSIDERATIONS — Should be taken 1-3 hours after meals.

CANADIAN BRAND NAMES — Diovol®; Diovol® Ex; Gelusil® Extra Strength; Mylanta™

INTERNATIONAL BRAND NAMES — Diovol (CA); Diovol Ex (CA); Gelusil Extra Strength (CA); Mylanta® (CA)