Antacids*

Drug	Available Strength	Dosage	Remarks
Aluminum hydroxide (Al[OH]₃)	600 mg/tab	1-2 tab PO 6 hourly	Adverse Reactions Constipation; phosphate depletion may occur with prolonged use or in large doses Special Instructions May be taken with or without food Contraindicated in hypophosphatemia Use with caution in chronic renal failure; may cause phosphate depletion To reduce constipating effects, aluminum hydroxide is often given with magnesium-containing antacid (eg Magnesium hydroxide, Magnesium oxide)
Magnesium hydroxide (Mg[OH])₂	400 mg/5 mL suspension	15 mL PO at bedtime	Adverse Reactions GI effects (diarrhea, abdominal cramps); hypermagnesemia in patients with renal impairment Special Instructions May be taken with or without food Contraindicated in intestinal obstruction, fecal impaction, renal failure Use with caution in colostomy, ileostomy, electrolyte imbalance Monitor for toxicity in patients with impaired renal function Usually given in combination with an aluminum-containing antacid to decrease diarrhea
Magnesium oxide	84.5 mg/cap	400 mg/day PO(Should be taken on an empty stomach)	Adverse Reactions GI effects (cramping, diarrhea, vomiting, upset stomach, paralytic ileus); Other effects (rashes, hives, itching, hypermagnesemia) Special Instructions Contraindicated in renal failure Use with caution in renal impairment, bowel obstruction Usually given in combination with an aluminum-containing antacid to decrease diarrhea
Intestinal Adsorbent
Bismuth salicylate (Bismuth subsalicylate)	262 mg/15 mL suspension; 262 mg/tab; 524 mg/tab	524 mg PO every 30 minutes-1 hour Max dose: 8 doses/day	Adverse Reactions Darkening of stool and tongue, hypersensitivity reactions Special Instructions Use with caution in patients with renal impairment Avoid in patients with salicylate or Aspirin sensitivity, history of severe GI bleeding and coagulopathy

*Various combinations of antacids are available. Al and Mg are usually combined to decrease constipation/diarrhea. Please see the latest MIMS for specific formulations and prescribing information.

Antidiarrheal

Drug

Dosage

Remarks

Dioctahedral smectite

<1 year: 3 g/day PO in 2-3 divided doses
1-2 years: 3-6 g/day PO in 2-3 divided doses
>2 years: 6-9 g/day PO in 2-3 divided doses

Adverse Reactions

May aggravate constipation

Special Instructions

May be diluted to or taken with water, milk, tea, food
Should not be used in patients with renal or hepatic impairment, fructose intolerance, glucose and galactose malabsorption syndrome, sucrase-isomaltase deficiency, acute dysentery with bloody stool and high fever, diarrhea associated with broad-spectrum antibiotic

Antiemetic

Drug

Dosage

Remarks

Alizapride

5 mg/kg/day PO in divided doses

Adverse Reactions

CNS effects (drowsiness, dizziness, headache, extrapyramidal symptoms [EPS]); Endocrine effects (amenorrhea, galactorrhea); GI effect (diarrhea)

Special Instructions

Contraindicated in Parkinson’s disease, GI perforation, pheochromocytoma
Use with caution in renal impairment
May impair ability to drive or operate machineries

Histamine2-Receptor Antagonists (H2RAs)

Drug	Dosage	Remarks
Cimetidine	>1 year: 20-25 mg/kg/day PO in divided doses	Adverse Reactions CNS effects (headache, dizziness, somnolence, insomnia, agitation); GI effects (diarrhea, nausea and vomiting); Musculoskeletal effects (myalgia, arthralgia); Other effect (rashes) Altered LFTs, reversible confusion in the elderly and those with renal failure have occasionally occurred Rarely reported effects: Hepatotoxicity, hypersensitivity reactions, CV effects (tachycardia, bradycardia, hypotension), hematologic effects (leukopenia, thrombocytopenia, agranulocytosis), acute pancreatitis Cimetidine has weak anti-androgenic effects; impotence and gynecomastia have occurred and are usually reversible Special Instructions Famotidine and Nizatidine may be taken with or without food All doses of Cimetidine should be taken with food IV injections should be given slowly; IV infusion is preferred (especially for high doses and in patients with CV impairment) Use with caution in patients with hepatic and renal impairment; dose adjustment recommended Cimetidine may reduce hepatic metabolism of some drugs through inhibition of cytochrome P450 isoenzymes; closely monitor those on oral anticoagulants, Lidocaine, Phenytoin or Theophylline; dose reduction may be necessary
Famotidine	Initial therapy: 20-40 mg PO 12 hourly x 6-12 weeks Maintenance therapy: 20 mg PO 12 hourly
Nizatidine	≥12 years: 150 mg PO 12 hourly for up to 8 weeks Max dose: 300 mg PO 24 hourly
Ranitidine	150 mg PO 12 hourly or 300 mg PO at bedtime for up to 8 weeks or 50 mg IM or slow IV for 1-2 minutes 6-8 hourly or intermittent IV infusion at 25 mg/hr for 2 hours repeated 6-8 hourly Severe cases: 150 mg PO 6 hourly x 12 weeks

Other Drugs Used in the Treatment of GERD*

Drug	Dosage	Remarks
Alginic acid/Al(OH)₃/Mg carbonate	1-2 tab PO 12 hourly (per tab: Alginic acid 200 mg/Al[OH]₃ 30 mg/Mg carbonate 40 mg) Max dose: 3 g of Al(OH)₃, 2g of Mg carbonate in a 24-hour period for <2 weeks	Adverse Reactions GI effects (diarrhea or constipation, abdominal distention, hiccups) Special Instructions Use with caution in patients with Na-restricted diet
Al(OH)₃-Mg carbonate/Attapulgite (activated)	1 sachet daily into a half glass of water after meals (per sachet: Al[OH]₃-Mg carbonate 0.5 g/Attapulgite [activated] 2.5 g)	Adverse Reactions Related to Aluminium: Phosphorus depletion during prolonged use or at high dosages Special Instructions Use with caution in patients bedridden or with megacolon (risk of scatoma) Take into account the dose of Aluminium in case of renal insufficiency and chronic dialysis (risk of encephalopathy) Avoid in patients with severe renal insufficiency and digestive tract stenosis
Na alginate/K bicarbonate	>12 years: 500-1,000 mg (Na alginate) PO Doses taken with food (after meals and at bedtime)	Adverse Reactions Skin rashes have been reported Special Instructions Use with caution in patients on Na-restricted diet, in patients <12 years old
Na alginate/Na bicarbonate/Ca carbonate	6-12 years: 250-500 mg (Na alginate) PO >12 years: 500-1,000 mg (Na alginate) PO Doses taken with food (after meals and at bedtime)	Adverse Reactions GI effect (abdominal distension) Special Instructions Use with caution in patients with Na- and Ca-restricted diet, in heart failure and renal dysfunction May be used during pregnancy and lactation

*Various combinations are available. Please see the latest MIMS for specific formulations and prescribing information.

Propulsives

Drug	Dosage	Remarks
Cisapride	Initial therapy: 0.2-0.8 mg/kg PO 6-8 hourly Max dose: 20 mg/day Doses to be taken 15 minutes before meals	Adverse Reactions CNS effects (dizziness, depression); CV effect (chest pain); GI effects (nausea, abdominal cramps, borborygmi, diarrhea); Other effects (fatigue, lower back pain, rash, pruritus, angioedema, bronchospasm) Special Instructions Contraindicated in GI hemorrhage, obstruction and perforation Use with caution in arrhythmias, ventricular tachycardia, ventricular fibrillation, history of heart disease, CHF, renal impairment, hypocalcemia, hypomagnesemia, respiratory disorders
Domperidone¹	0.25-0.5 mg/kg body wt PO 6-8 hourly Doses to be taken 15-30 minutes before meals and at bedtime	Adverse Reactions GI effects (abdominal cramps, abnormal liver function tests, dry mouth); Endocrine effects (elevated prolactin levels, galactorrhea, gynecomastia); Dermatologic effects (urticaria, rash); CNS effects (extrapyramidal reactions, drowsiness, headache) Associated with increased risk of ventricular arrhythmia or sudden cardiac death, particularly with doses >30 mg/day Special Instructions Use the lowest effective dose for the shortest duration necessary Use with caution in patients with renal or mild hepatic impairment Avoid in patients with prolactinoma, GI perforation, hemorrhage or obstruction, moderate or severe hepatic impairment, significant electrolyte disturbances, known existing prolongation of cardiac conduction intervals (particularly QTc), underlying cardiac disease, concomitant use of QT-prolonging drugs or CYP3A4 inhibitors
Metoclopramide	<1 year: : 0.1 mg/kg PO 12 hourly 1-6 years: 0.1 mg/kg PO 8-12 hourly >6 years: Max dose: 0.5 mg/kg/day in 2 divided doses Doses should be taken at least 15 minutes before meals	Adverse Reactions CNS effects (restlessness, drowsiness, headache, extrapyramidal reactions and dystonic reactions have been reported eg tardive dyskinesia and parkinsonian symptoms); Endocrine effects (increased prolactin resulting in galactorrhea or gynecomastia); GI effect (diarrhea) Special Instructions Avoid in patients in whom stimulation of muscular contractions may adversely affect GI conditions (eg GI hemorrhage, obstruction, perforation) Should be avoided in patients with pheochromocytoma, epilepsy, Parkinson’s disease, history of depression and in patients taking drugs that can also cause extrapyramidal symptoms Use with caution in patients with renal or hepatic impairment

¹Combination with Pantoprazole is available. Please see the latest MIMS for specific formulations and prescribing information.

Proton Pump Inhibitors (PPIs)

Drug	Dosage	Remarks
Dexlansoprazole	>12 years: 30 mg PO 24 hourly x 4 weeks	Adverse Reactions Generally well tolerated; most commonly reported: Headache, diarrhea, rash Less common: GI effects (constipation, flatulence, abdominal pain, nausea/vomiting, dry mouth); Dermatologic effects (pruritus, urticaria); Musculoskeletal effects (arthralgia, myalgia); Other effects (dizziness, fatigue, insomnia, cough, upper respiratory tract infection) Hypersensitivity reactions, elevated liver enzymes, and isolated cases of photosensitivity and hepatotoxicity have been reported Special Instructions Use with caution in patients with hepatic impairment; dose adjustment recommended Concomitant use with Atazanavir or Nelfinavir is not recommended (PPIs reduce exposure to these drugs) Exclude possibility of gastric malignancy prior to treatment Bone fracture: Several published observational studies suggest that PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist or spine. Patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated
Esomeprazole	1-11 years with <20 kg body wt: 10 mg PO/IV 24 hourly x 8 weeks 1-11 years with ≥20 kg body wt: 10-20 mg PO/IV 24 hourly x 8 weeks ≥12 years: 20 mg PO/IV 24 hourly
Lansoprazole	1-11 years with <30 kg body wt: 15 mg PO 24 hourly x up to 12 weeks 1-11 years with >30 kg body wt: 30 mg PO 24 hourly x up to 12 weeks ≥12 years: Initial therapy: 30 mg PO 24 hourly x 4-8 weeks or 30 mg IV (over 30 minutes) 24 hourly x 7 days Maintenance therapy: 15 mg PO 24 hourly
Omeprazole¹	≥1 year with 5-10 kg body wt: 5 mg PO 24 hourly x 2-4 weeks ≥1 year with 10-20 kg body wt: 10 mg PO 24 hourly x 2-4 weeks ≥1 year with >20 kg body wt: 20 mg PO 24 hourly x 2-4 weeks
Pantoprazole²	≥5 years with 15-40 kg body wt: 20 mg PO 24 hourly x 4-8 weeks ≥12 years: Initial therapy: 20 mg PO 24 hourly Maintenance therapy: 20 mg PO 24 hourly May increase to 40 mg/day for relapse; reduce dose to 20 mg/day once relapse resolves
Rabeprazole (Na rabeprazole, Sodium rabeprazole)	1-11 years with <15 kg body wt: 5-10 mg PO 24 hourly for up to 12 weeks >12 years: 20 mg PO 24 hourly in the morning x 8 weeks

¹Combination with Sodium bicarbonate is available. Please see the latest MIMS for specific formulations and prescribing information.
²Combination with Domperidone is available. Please see the latest MIMS for specific formulations and prescribing information.

Disclaimer

All dosage recommendations are for children with normal renal and hepatic function unless otherwise stated.
Not all products are available or approved for above use in all countries.
Products listed in the Drug Summary are based on indications stated in the locally approved product monographs.
Please refer to local product monographs in Related MIMS Drugs for country-specific prescribing information.

Gastroesophageal Reflux Disease (GERD) in Children Drug Summary