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Prevacid Side Effects

Generic Name: lansoprazole

Note: This document contains side effect information about lansoprazole. Some of the dosage forms listed on this page may not apply to the brand name Prevacid.

For the Consumer

Applies to lansoprazole: oral capsule delayed release, oral packet, oral powder for suspension, oral tablet disintegrating delayed release

Along with its needed effects, lansoprazole (the active ingredient contained in Prevacid) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking lansoprazole:

More Common

Less Common

  • Increased or decreased appetite
  • joint pain
  • nausea
  • stomach pain
  • vomiting


Incidence Not Known

  • Back or leg pains
  • bleeding gums
  • blistering, peeling, or loosening of the skin
  • bloating
  • bloody, black, or tarry stools
  • change in mental status
  • chest pain
  • chills
  • clay colored stools
  • cough or hoarseness
  • dark or bloody urine
  • difficulty with swallowing
  • drowsiness
  • fast heartbeat
  • fever
  • general body swelling
  • high fever
  • hives
  • indigestion
  • loss of appetite
  • lower back or side pain
  • mood or mental changes
  • muscle spasms (tetany) or twitching seizures
  • nosebleeds
  • painful or difficult urination
  • pains in the stomach, side, or abdomen, possibly radiating to the back
  • pale skin
  • pinpoint red spots on the skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • red skin lesions, often with a purple center
  • red, irritated eyes
  • seizures
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • stomach tenderness
  • swelling of the feet or lower legs
  • swollen or painful glands
  • tightness in the chest
  • trembling
  • unusual tiredness or weakness
  • yellow eyes or skin

Some side effects of lansoprazole may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More Common

Less Common

  • Bleeding, blistering, burning, coldness, or discoloration of the skin
  • mild nausea


  • Bad, unusual, or unpleasant (after) taste
  • belching
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • change in taste
  • feeling faint, dizzy, or lightheaded
  • feeling of heat or warmth
  • flushing or redness of the skin, especially on the face and neck
  • mild diarrhea
  • mild headache
  • mild vomiting
  • stomach discomfort or upset
  • sweating

Incidence Not Known

  • Decrease in passing urine (dribbling)
  • decrease in the frequency of urination
  • decrease in urine volume
  • difficulty with speaking

For Healthcare Professionals

Applies to lansoprazole: compounding powder, intravenous powder for injection, oral delayed release capsule, oral granule for reconstitution, oral suspension, oral tablet disintegrating


The most commonly reported side effects include headache, dizziness, fatigue, and malaise.[Ref]


Pseudomembranous colitis may occur with triple therapy for the eradication of H. pylori.

The majority of patients with severe/protracted cases of diarrhea who discontinued treatment had symptom resolution.[Ref]

Common (1% to 10%): Nausea, diarrhea, stomachache/abdominal pain/epigastric discomfort, constipation, vomiting, dry/sore mouth/throat, flatulence, benign fundic gland polyps

Rare (0.01% to 0.1%): Glossitis, candidiasis of the esophagus, taste disturbances, pancreatitis

Very rare (less than 0.01%): Macroscopic/microscopic colitis, stomatitis

Frequency not reported: Dyspepsia, pseudomembranous colitis, abdomen enlarged, halitosis, abnormal stools, bezoar, cardiospasm, dysphagia, enteritis, eructation, esophageal stenosis/ulcers/disorder, esophagitis, fecal discoloration, gastric nodules, gastritis, gastroenteritis, gastrointestinal anomaly/disorder/hemorrhage, gum hemorrhage, hematemesis, hiatal hernia, impaired gastric emptying, increased salivation, melena, mouth ulceration, gastrointestinal moniliasis, rectal disorder/hemorrhage, tongue disorder, ulcerative colitis/stomatitis, tenesmus, duodenitis, positive fecal occult blood

Postmarketing reports: Clostridium difficile associated diarrhea[Ref]


Common (1% to 10%): Urticaria, pruritus/itching, rash

Rare (0.01% to 0.1%): Petechia, hair loss/thinning/alopecia, erythema multiforme, photosensitivity, hyperhidrosis/sweating

Very rare (less than 0.01%): Steven-Johnson syndrome, toxic epidermal necrolysis/fatal toxic epidermal necrolysis

Frequency not reported: Subacute cutaneous lupus erythematosus (erythematous/bullous rashes), acne, contact dermatitis, dry skin, fixed eruption, hair disorder, maculopapular rash, nail disorder, skin disorder[Ref]

Skin rashes, urticaria, and pruritus generally resolved upon discontinuation of therapy.[Ref]

Nervous system

Common (1% to 10%): Headache, dizziness

Rare (0.01% to 0.1%): Vertigo, paresthesia, taste disturbance/loss/perversion, somnolence, tremor

Frequency not reported: Cerebrovascular accident/cerebral infarction, migraine, amnesia, convulsion, dementia, hemiplegia, hyperkinesia, hypertonia, hypesthesia, parosmia

Postmarketing reports: Speech disorder[Ref]


Common (1% to 10%): Increased liver enzyme levels (ALT, AST, GGTP, alkaline phosphatase)

Rare (0.01% to 0.1%): Hepatitis, jaundice

Frequency not reported: Cholelithiasis, bilirubinemia

Postmarketing reports: Hepatotoxicity[Ref]


Common (1% to 10%): Fatigue

Rare (0.01% to 0.1%): Fever

Frequency not reported: Asthenia, candidiasis, flu syndrome, infection (not otherwise specified), chills, malaise, pain, thirst, deafness, ear disorder, otitis media, tinnitus, metaplasia, increased globulins, additional isolated laboratory abnormalities[Ref]


Uncommon (0.1% to 1%): Fracture of the hip/wrist/spine, arthralgia, myalgia

Frequency not reported: Back pain, neck pain, neck rigidity, arthritis, bone/joint disorder, leg cramps, musculoskeletal pain, myasthenia, synovitis

Postmarketing reports: Myositis, systemic lupus erythematosus[Ref]


Uncommon (0.1% to 1%): Thrombocytopenia, eosinophilia, leukopenia

Rare (0.01% to 0.1%): Anemia, purpura

Very rare (less than 0.01%): Agranulocytosis, pancytopenia

Frequency not reported: Neutropenia, bruising, hemolysis, lymphadenopathy, increased/decreased/abnormal WBC, abnormal AG ratio, abnormal RBC, hemoglobin decreased, increased/decreased/abnormal platelets

Postmarketing reports: Aplastic anemia, hemolytic anemia, thrombotic thrombocytopenic purpura[Ref]


Uncommon (0.1% to 1%): Depression

Rare (0.01% to 0.1%): Insomnia, hallucination, confusion, restlessness

Frequency not reported: Abnormal dreams, agitation, anxiety, apathy, depersonalization, emotional lability, hostility aggravated, libido increased/decreased, nervousness, neurosis, sleep disorder, abnormal thinking[Ref]


Uncommon (0.1% to 1%): Edema

Frequency not reported: Peripheral edema, chest pain (not otherwise specified), contusion, angina, arrhythmia, bradycardia, hypotension, hypertension, myocardial infarction, palpitations, shock/circulatory failure, syncope, tachycardia, vasodilation[Ref]


Rare (0.01% to 0.1%): Impotence

Frequency not reported: Urinary tract infection, pelvic pain, abnormal menses, breast enlargement/pain/tenderness, dysmenorrhea, dysuria, leukorrhea, menorrhagia, menstrual disorder, penis disorder, polyuria, testis disorder, urethral pain, urinary frequency/retention/urgency, urination impaired, vaginitis, crystal urine present, albuminuria, hematuria[Ref]


A definitive relationship between use of this drug and hyponatremia has not been established.[Ref]

Rare (0.01% to 0.1%): Anorexia

Very rare (less than 0.01%): Increased cholesterol/triglyceride levels, hyponatremia

Frequency not reported: Hypomagnesemia, increased appetite, diabetes mellitus, avitaminosis, gout, dehydration, hyperglycemia/hypoglycemia, weight gain/loss, blood potassium increased, decreased cholesterol, increased LDH, hyperlipemia, hunger, increased/decreased electrolytes[Ref]


Rare (0.01% to 0.1%): Visual disturbances

Frequency not reported: Ptosis, diplopia, abnormal vision, amblyopia, blepharitis, blurred vision, cataract, conjunctivitis, dry eyes, eye disorder/pain, glaucoma, photophobia, retinal degeneration/disorder, visual field defect[Ref]


Rare (0.01% to 0.1%): Interstitial nephritis

Frequency not reported: Renal failure/impairment, kidney calculus, kidney pain, increased creatinine, blood urea increased, glycosuria[Ref]

Some cases of interstitial nephritis resulted in renal failure.[Ref]


Rare (0.01% to 0.1%): Gynecomastia

Frequency not reported: Goiter, hypothyroidism, increased glucocorticoids, increased gastrin levels[Ref]


Rare (0.01% to 0.1%): Angioedema

Very rare (less than 0.01%): Anaphylaxis/anaphylactic shock

Frequency not reported: Allergic reaction

Postmarketing reports: Anaphylactoid reactions[Ref]


A definitive relationship between use of this drug and interstitial pneumonia has not been established.[Ref]

Frequency not reported: Wheezing, upper respiratory tract inflammation/infection, interstitial pneumonia, asthma, bronchitis, cough increased, dyspnea, epistaxis, hemoptysis, hiccup, hoarseness, lung fibrosis, pharyngitis, pleural disorder, pneumonia, respiratory disorder, rhinitis, sinusitis, stridor[Ref]


Frequency not reported: Carcinoma/skin carcinoma, laryngeal neoplasia[Ref]


1. "Product Information. Prevacid (lansoprazole)." TAP Pharmaceuticals Inc, Deerfield, IL.

2. Ministerio de Sanidad y Consumo. Gobierno de España "AEMPS. Agencia Española de Medicamentos y Productos Sanitarios. Available from: URL:"

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

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.