ND Clinical Board Review: Ranitidine

Today's med: Ranitidine (ra NI ti deen)

(brand name: Zantac, Index term: Ranitidine Hydrochloride)

Drug Class: Histamine H2 Antagonist

Other Drugs in this class: Famotidine, Cimetidine, Nizatidine,Ranitidine hydrochloride, Ibuprofen/Famotidine, Cimetidine hydrochloride,Famotidine/Magnesium hydroxide/Carbonate ion

Indications: Zantac®: Short-term and maintenance therapy of duodenal ulcer, gastric ulcer, gastroesophageal reflux disease (GERD), active benign ulcer, erosive esophagitis, and pathological hypersecretory conditions; as part of a multidrug regimen for H. pylori eradication to reduce the risk of duodenal ulcer recurrence.

Zantac 75® [OTC]: Relief of heartburn, acid indigestion, and sour stomach

Use: Unlabeled: Recurrent postoperative ulcer, upper GI bleeding, prevention of acid-aspiration pneumonitis during surgery, and prevention of stress-induced ulcers.

Contraindications: Hypersensitivity to Ranitidine or any component of the formulation

Adverse Effects: Cardiovascular: Asystole, atrioventricular block, bradycardia (with rapid I.V. administration), premature ventricular beats, tachycardia, vasculitis

Central nervous system: Agitation, dizziness, depression, hallucinations, headache, insomnia, malaise, mental confusion, somnolence, vertigo

Dermatologic: Alopecia, erythema multiforme, rash

Endocrine & metabolic: Prolactin levels increased

Gastrointestinal: Abdominal discomfort/pain, constipation, diarrhea, nausea, necrotizing enterocolitis (VLBW neonates; Guillet, 2006), pancreatitis, vomiting

Hematologic: Acquired immune hemolytic anemia, acute porphyritic attack, agranulocytosis, aplastic anemia, granulocytopenia, leukopenia, pancytopenia, thrombocytopenia

Hepatic: Cholestatic hepatitis, hepatic failure, hepatitis, jaundice

Local: Transient pain, burning or itching at the injection site

Neuromuscular & skeletal: Arthralgia, involuntary motor disturbance, myalgia

Ocular: Blurred vision

Renal: Acute interstitial nephritis, serum creatinine increased

Respiratory: Pneumonia (causal relationship not established)

Miscellaneous: Anaphylaxis, angioneurotic edema, hypersensitivity reactions (eg, bronchospasm, fever, eosinophilia)

Standard Dosing: Adults: Duodenal ulcer: Oral: Treatment: 150 mg twice daily, or 300 mg once daily after the evening meal or at bedtime; maintenance: 150 mg once daily at bedtime Helicobacter pylori eradication: 150 mg twice daily; requires combination therapy

Pathological hypersecretory conditions:

Oral: 150 mg twice daily; adjust dose or frequency as clinically indicated; doses of up to 6 g/day have been used

I.V.: Continuous infusion for Zollinger-Ellison: Initial: 1 mg/kg/hour; measure gastric acid output at 4 hours, if >10 mEq or if patient is symptomatic, increase dose in increments of 0.5 mg/kg/hour; doses of up to 2.5 mg/kg/hour (or 220 mg/hour) have been used

Gastric ulcer, benign: Oral: 150 mg twice daily; maintenance: 150 mg once daily at bedtime

GERD: Oral: 150 mg twice daily

Erosive esophagitis: Oral: Treatment: 150 mg 4 times/day; maintenance: 150 mg twice daily

Prevention of heartburn: Oral: Zantac 75® [OTC]: 75 mg 30-60 minutes before eating food or drinking beverages which cause heartburn; maximum: 150 mg in 24 hours; do not use for more than 14 days

Stress ulcer prophylaxis (unlabeled use; ASHP, 1999): Note: Intended for patients with associated risk factors (eg, coagulopathy, mechanical ventilation for >48 hours, severe sepsis); discontinue use once risk factors have resolved.

Oral, nasogastric (NG) tube: 150 mg twice daily

I.V.: Intermittent bolus: 50 mg every 6-8 hours

Patients not able to take oral medication:

I.M.: 50 mg every 6-8 hours

I.V.: Intermittent bolus or infusion: 50 mg every 6-8 hours

Continuous I.V. infusion: 6.25 mg/hour

Elderly: Ulcer healing rates and incidence of adverse effects are similar in the elderly, when compared to younger patients; dosing adjustments not necessary based on age alone

Ranitidine injection may be administered I.M. or I.V.:

I.M.: Injection is administered undiluted

I.V.: Must be diluted; may be administered I.V. push, intermittent I.V. infusion, or continuous I.V. infusion

I.V. push: Manufacturer recommends a maximum rate of administration of 10 mg/minute (or over 5 minutes); however, may also be administered at a maximum rate of 25 mg/minute (or over 2 minutes) if necessary (Coursin, 1988; Goelzer, 1988; Smith, 1987).

Intermittent I.V. infusion: Administer over 15-20 minutes

Continuous I.V. infusion: Titrate dosage based on gastric pH.

EFFERdose®: Should not be chewed, swallowed whole, or dissolved on tongue: 25 mg tablet: Dissolve in at least 5 mL of water; wait until completely dissolved before administering

Drug interactions: LINK: http://www.drugs.com/drug-interactions/ranitidine.html

A total of 271 drugs (1742 brand and generic names) are known to interact with ranitidine.