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Zantac 150 EFFERdose Side Effects

Generic Name: ranitidine

Note: This page contains side effects data for the generic drug ranitidine. It is possible that some of the dosage forms included below may not apply to the brand name Zantac 150 EFFERdose.

For the Consumer

Applies to ranitidine: oral solution, oral tablets and tablets for, oral tablets effervescent for solution, parenteral injection, parenteral injection for iv infusion only

Side effects include:

Oral or parenteral therapy: Headache, sometimes severe.

IM therapy: Transient pain at injection site.

IV therapy: Transient local burning or itching.

For Healthcare Professionals

Applies to ranitidine: compounding powder, injectable solution, intravenous solution, oral capsule, oral granule effervescent, oral syrup, oral tablet, oral tablet effervescent


Ranitidine (the active ingredient contained in Zantac 150 EFFERdose) is generally well tolerated.[Ref]


Gastrointestinal side effects have included constipation, nausea/vomiting, diarrhea, abdominal pain, and rare reports of pancreatitis. Rebound acid hypersecretion has been reported after discontinuation of therapy. A case report of coinfection with Giardia lamblia and Clostridium difficile has been attributed to the achlorhydria induced by ranitidine (the active ingredient contained in Zantac 150 EFFERdose) predisposing the patient to the enteric infection.[Ref]


Cardiovascular side effects have rarely included tachycardia, bradycardia, atrioventricular block, and premature ventricular beats. Several cases of bradycardia following intravenous administration of ranitidine (the active ingredient contained in Zantac 150 EFFERdose) have been reported. Ranitidine-induced bradycardia may be due to a rise in the serum histamine concentration or due to a direct effect of ranitidine on cardiac H2 receptors.[Ref]

Nervous system

Nervous system side effects have been reported rarely. These have included headache (sometimes severe), somnolence, dizziness, malaise, and vertigo. Reversible mental confusion, agitation, depression, and hallucinations have been reported, predominantly in severely ill elderly patients. Hostility, mania, mental status changes, dystonia, reversible involuntary motor disturbances have also been reported.[Ref]

The mechanism by which ranitidine induces mental status changes is not well established but appears to involve increased serum concentrations of ranitidine. Renal dysfunction, advanced age, and critical illness appear to be associated with an increased risk of central nervous system toxicity. Onset of symptoms is typically within the first few weeks of therapy, but may be delayed. Following discontinuation of ranitidine, mental status usually normalizes over several days.[Ref]


Two cases of toxic epidermal necrolysis have been reported in patients with underlying idiopathic thrombocytopenia purpura. A 72-year-old male also experienced a photosensitivity reaction that resolved after ranitidine (the active ingredient contained in Zantac 150 EFFERdose) was discontinued.[Ref]

Dermatologic side effects have included alopecia, rash, pruritus, contact dermatitis, erythema multiforme, cutaneous vasculitis, and toxic epidermal necrolysis.[Ref]


Musculoskeletal side effects have included arthralgias and myalgias.[Ref]


Overall, serious hepatotoxicity due to ranitidine (the active ingredient contained in Zantac 150 EFFERdose) is rare. Hepatocellular, hepatocanalicular, and mixed-type injury have been reported. In most cases, hepatotoxicity has been associated with fever, chills, nausea, and occasionally rash and eosinophilia, with onset of symptoms early in the course of therapy. Such symptomatology is suggestive of a hypersensitivity etiology. The majority of cases resolve following discontinuation of ranitidine therapy although, at least two fatalities have been reported.

In a study with healthy volunteers , SGPT values were increased to at least twice the pretreatment levels in 6 of 12 subjects receiving 100 mg intravenously four times daily for 7 days, and in 4 of 24 subjects receiving 50 mg intravenously four times daily for 5 days.[Ref]

Hepatic side effects have included transient and minor increases in serum transaminases, which may be important in patients with liver disease. There are rare reports of ranitidine-induced hepatitis with or without jaundice, one case of subfulminant hepatitis with a fatal outcome, and very rare cases of acute interstitial nephritis.[Ref]


Other reported side effects have included tiredness and one case of aseptic meningitis.[Ref]


Hypersensitivity side effects have included rash, urticaria, bronchospasm, fever, eosinophilia, angioneurotic edema, acute eosinophilic pneumonia and anaphylaxis. Vasculitis associated with immune complexes has also been reported.[Ref]


Renal side effects have included mild elevations in serum creatinine. Rare cases of interstitial nephritis and Fanconi's syndrome have been reported.[Ref]


Respiratory side effects have included an increased risk of developing pneumonia in patients taking H2 receptor antagonists versus those who had stopped treatment. However, a causal relationship has not been established.[Ref]


Ocular side effects have included blurred vision and increased intraocular pressure in a patient with a history of glaucoma.[Ref]


Hematologic side effects have included leukopenia, granulocytopenia, and thrombocytopenia in a few patients. These were usually reversible. Rare cases of agranulocytosis, pancytopenia, sometimes with marrow hypoplasia, aplastic anemia, and acquired immune hemolytic anemia have been reported.[Ref]

Serious hematologic abnormalities are rare. Patients with renal dysfunction or those who are critically ill may be at increased risk. While the mechanism of bone marrow toxicity is unknown, ranitidine concentration-dependent inhibition of hematopoietic progenitor cell activity and hypersensitivity have both been proposed. Hematologic abnormalities typically resolve upon discontinuation of ranitidine therapy.

Cases of ranitidine-induced thrombocytopenia are typically immune-mediated.[Ref]


Endocrine side effects have been reported rarely. These have included gynecomastia, impotence, and loss of libido in male patients, although, the incidence was similar to that in the general population. Hyperprolactinemia, amenorrhea, reductions in circulating levothyroxine and hypergastrinemia have also been reported.[Ref]

Ranitidine does not possess antiandrogenic properties nor has it been associated with significant changes in pituitary hormone concentrations under study conditions. However, increases in prolactin serum concentrations following administration of high doses as well as decreases in levothyroxine serum concentrations during short-term therapy have been reported. Thyroid hormone levels are not affected during long-term therapy.[Ref]


1. "Product Information. Zantac 75 (ranitidine)." Pfizer U.S. Pharmaceuticals, New York, NY.

2. Cerner Multum, Inc. "Australian Product Information." O 0

3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

4. "Product Information. Zantac (ranitidine)." Glaxo Wellcome, Research Triangle Park, NC.

It is possible that some side effects of Zantac 150 EFFERdose may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.