Disclaimer to the On-line Edition
This Manual has been designed for use in the NICU at London Health Sciences Centre (LHSC), London, Ontario, Canada, and represents clinical practice at this institution. The information contained within the Manual may not be applicable to other centres. If users of this Manual are not familiar with a drug, it is recommended that the official monograph be consulted before it is prescribed and administered. Any user of this information is advised that the contributors, Editor and LHSC are not responsible for any errors or omissions, and / or any consequences arising from the use of the information in this Manual.



  • treatment of duodenal, gastric or "stress" ulcers and upper GI bleeding


  • antagonist of histamine at gastric H2 receptors
  • inhibits both basal gastric acid secretion and gastric acid secretion induced by histamine, pentagastrin, food, insulin and amino acids
  • use with caution in infants with liver or kidney disease. Approximately 70% of an IV dose in excreted in urine as unchanged drug. Orally administered ranitidine undergoes extensive metabolism on first pass through the liver.

Side Effects

  • rare and usually mild
  • most frequent are GI (diarrhea, constipation, abdominal discomfort and pain)
  • agitation or drowsiness can occur
  • rash; urticaria at site of injection
  • tachycardia and bradycardia have been reported, but are rare
  • increases in liver enzymes have also been seen


  • IV: 0.5 to 1 mg/kg q12h
  • may increase to 1.5 mg/kg q6h
  • give by slow infusion
  • must be diluted to 1mg/mL for IV administration
  • PO: 1 to 2 mg/kg q12h
  • may increase to 2 mg/kg q8h

Gastroesophageal Reflux:

an oral dose of 5 mg/kg, twice daily, has been used for the treatment of gastroesophageal reflux in young infants (6 weeks to 6 months of age). The authors suggested that the dose be administered 2 hours after feeding. (1)


  • a continuous IV infusion (0.2 mg/kg/h for 37 hours) was used successfully in a 30 week old infant who had an acute gastrointestinal bleed secondary to tolazoline and indomethacin. Ranitidine accumulated in the serum after 24 hours; the authors felt that this dose, although effective, was excessive.


  • 1 mg/mL syringe, prepared by Pharmacy
  • 15 mg/mL oral solution
  • 25 mg/mL, 2mL ampoule (must be diluted to 1 mg/mL)
  • to DILUTE the 25 mg/mL solution to 1 mg/mL:
    1. withdraw 0.5 mL of 25 mg/mL solution (this volume contains 12.5mg)
    2. add volume from i) to 12 mL with sterile water for injection
    3. final concentration = 12.5 mg/12.5 mL
                                   = 1 mg/mL


  1. Mallet E, Mouterde O, Dubois F, Flipo LJ, Moore N : Use of ranitidine in young infants with gastro-oesophageal reflux. Eur J Clin Pharmacol 1989;36:641-2.
  2. McEvoy G K (ed): AHFS Drug Information, American Society of Hospital Pharmacists, 1991.
  3. Gomella TL (Ed): Neonatology - Management, Procedures, On-Call Problems, Diseases, Drugs, 1992, Appleton and Lange, Norwalk, Connecticut.
  4. Milan EM and McFeely EJ: Memory Bank for Neonatal Drugs, 1990, Williams and Wilkins, Baltimore.
  5. Rosenthal M and Miller PW: Ranitidine in the newborn, Archives of Disease in Childhood 1988; 63: 88-89.
  6. Hyman PE, Garvey TQ and Abrams CE: Tolerance to intravenous ranitidine, The Journal of Pediatrics 1987; 110: 794-796.
  7. Blumer JL, Rothstein FC, Kaplan BS et al: Pharmacokinetic determination of ranitidine pharmacodynamics in pediatric ulcer disease, The Journal of Pediatrics 1985; 107: 301-306.
  8. Hyman PE, Garvey TQ and Harada T: Effect of ranitidine on gastric acid hypersecretion in an infant with short bowel syndrome, Journal of Pediatric Gastroenterology and Nutition 1985; 4: 316-319.
  9. Young TE and Mangum OB: Neofax - A Manual of Drugs Used in Neonatal Care, Columbus, Ohio: Ross Laboratories, 1992.

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