Side Effects of Nexium (esomeprazole)

Nexium (esomeprazole) is a proton pump inhibitor (PPI) which block the production of acid by the stomach and are used to treat conditions such as stomach and duodenal ulcers, gastroesophageal reflux disease (GERD) and the Zollinger-Ellison syndrome which all are caused by stomach acid. 

Nexium, like other proton-pump inhibitors, blocks the enzyme in the wall of the stomach that produces acid. By blocking the enzyme, the production of acid is decreased, and this allows the stomach and esophagus to heal. Nexium 24 hour is available over-the-counter (OTC) without a prescription. 

Common side effects of Nexium include

• diarrhea,
• nausea,
• vomiting,
• headaches,
• rash and
• dizziness.

Serious side effects of Nexium include

• nervousness,
• abnormal heartbeat,
• muscle pain,
• weakness,
• leg cramps, and
• water retention occur infrequently.

Proton pump inhibitors may increase the risk of Clostridium difficile infection. High doses and long-term use (1 year or longer) may increase the risk of osteoporosis-related fractures of the hip, wrist, or spine; reduced absorption of vitamin B12 (cyanocobalamin); low levels of magnesium (hypomagnesemia); and increased risk of heart attacks.

Drug interactions of Nexium include diazepam, because Nexium potentially can increase the concentration of diazepam in blood by decreasing the elimination of diazepam in the liver.

• The absorption of certain drugs may be affected by stomach acidity.
• Therefore, Nexium and other PPIs that reduce stomach acid also reduce the absorption and concentration in blood of ketoconazole and increase the absorption and concentration in blood of digoxin. This may lead to reduced effectiveness of ketoconazole or increased digoxin toxicity, respectively.
• Through unknown mechanisms, Nexium may increase blood levels of saquinavir and reduce blood levels of nelfinavir and atazanavir. Therefore, nelfinavir or atazanavir should not be administered with Nexium, and physicians should consider reducing the dose of saquinavir in order to avoid side effects from saquinavir.
• Clopidogrel is converted to its active form by enzymes in the liver. Nexium reduces the activity of these enzymes and potentially can reduce the activity of clopidogrel. Nexium should not be used with clopidogrel.
• Nexium increases the concentration of cilostazol and its metabolites. The dose of cilostazol should be reduced from 100 mg twice daily to 50 mg twice daily when given with esomeprazole. Nexium may increase blood levels of methotrexate and tacrolimus. 

Use of Nexium in pregnant women has not been adequately evaluated. Nexium has not been adequately studied in nursing women. Consult your doctor before breastfeeding.

Esomeprazole, like other PPIs, is well-tolerated. The most common side effects are

• diarrhea,
• nausea,
• vomiting,
• headaches,
• rash and
• dizziness.

Nervousness, abnormal heartbeat, muscle pain, weakness, leg cramps, and water retention occur infrequently.

Proton pump inhibitors may increase the risk of Clostridium difficile infection. High doses and long-term use (1 year or longer) may increase the risk of osteoporosis-related fractures of the hip, wrist, or spine. Prolonged use also reduces absorption of vitamin B12 (cyanocobalamin).

Long-term use of PPIs has also been associated with low levels of magnesium (hypomagnesemia). Analysis of patients taking PPIs for long periods of time showed an increased risk of heart attacks.

Therefore, it is important to use the lowest doses and shortest duration of treatment necessary for the condition being treated.

The following serious adverse reactions are described below and elsewhere in labeling:

• Acute Interstitial Nephritis
• Clostridium difficile-Associated Diarrhea
• Bone Fracture
• Cutaneous and Systemic Lupus Erythematosus
• Hypomagnesemia
• Fundic Gland Polyps

Clinical Trials Experience With Intravenous Nexium

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Adults

The safety of intravenous esomeprazole is based on results from clinical trials conducted in four different populations including patients having symptomatic GERD with or without a history of erosive esophagitis (n=199), patients with erosive esophagitis (n=160), healthy subjects (n=204) and patients with bleeding gastric or duodenal ulcers (n=375).

Symptomatic GERD And Erosive Esophagitis Trials

The data described below reflect exposure to Nexium I.V. for Injection in 359 patients. Nexium I.V. for Injection was studied only in actively-controlled trials. The population was

• 18 to 77 years of age;
• 45% Male, 52% Caucasian,
• 17% Black,
• 3% Asian,
• 28% Other, and
• had either
  • erosive reflux esophagitis (44%) or
  • GERD (56%).

Most patients received doses of either 20 or 40 mg either as an infusion or an injection. Adverse reactions occurring in ≥1% of patients treated with intravenous esomeprazole (n=359) in clinical trials are listed below:

Table 2: Adverse Reactions Occurring at an Incidence ≥ 1% in the Nexium I.V. Group

Intravenous treatment with esomeprazole 20 and 40 mg-administered as an injection or as an infusion was found to have a safety profile similar to that of oral administration of esomeprazole.

Pediatric

A randomized, open-label, multi-national study to evaluate the pharmacokinetics of repeated intravenous doses of once daily esomeprazole in pediatric patients 1 month to 17 years old, inclusive was performed. The safety results are consistent with the known safety profile of esomeprazole and no unexpected safety signals were identified.

Risk Reduction Of Rebleeding Of Gastric Or Duodenal Ulcers In Adults

The data described below reflect exposure to Nexium I.V. for Injection in 375 patients. Nexium I.V. for Injection was studied in a placebo-controlled trial. Patients were randomized to receive Nexium I.V. for Injection (n=375) or placebo (n=389). The population was 18 to 98 years old; 68% Male, 87% Caucasian, 1% Black, 7% Asian, 4% other, who presented with endoscopically confirmed gastric or duodenal ulcer bleeding.

Following endoscopic hemostasis, patients received either 80 mg esomeprazole as an intravenous infusion over 30 minutes followed by a continuous infusion of 8 mg per hour or placebo for a total treatment duration of 72 hours. After the initial 72-hour period, all patients received oral proton pump inhibitor (PPI) for 27 days.

Table 3: Incidence (%) of Adverse Reactions that Occurred in Greater than 1 % of Patients within 72 Hours after Start of Treatment¹

With the exception of injection site reactions described above, intravenous treatment with esomeprazole administered as an injection or as an infusion was found to have a safety profile similar to that of oral administration of esomeprazole.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Nexium. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Postmarketing Reports - There have been spontaneous reports of adverse events with postmarketing use of esomeprazole. These reports occurred rarely and are listed below by body system:

• Blood And Lymphatic System Disorders: agranulocytosis, pancytopenia;
• Eye Disorders: blurred vision;
• Gastrointestinal Disorders: pancreatitis; stomatitis; microscopic colitis; fundic gland polyps;
• Hepatobiliary Disorders: hepatic failure, hepatitis with or without jaundice;
• Immune System Disorders: anaphylactic reaction/shock; systemic lupus erythematosus;
• Infections and Infestations: GI candidiasis;
• Metabolism and nutritional disorders: hypomagnesemia with or without hypocalcemia and/or hypokalemia;
• Musculoskeletal And Connective Tissue Disorders: muscular weakness, myalgia, bone fracture;
• Nervous System Disorders: hepatic encephalopathy, taste disturbance;
• Psychiatric Disorders: aggression, agitation, depression, hallucination;
• Renal and Urinary Disorders: interstitial nephritis;
• Reproductive System and Breast Disorders: gynecomastia;
• Respiratory, Thoracic and Mediastinal Disorders: bronchospasm;
• Skin and Subcutaneous Tissue Disorders: alopecia, erythema multiforme, hyperhidrosis, photosensitivity, Stevens-Johnson syndrome, toxic epidermal necrolysis (TEN, some fatal), cutaneous lupus erythematosus.

Other adverse events not observed with Nexium, but occurring with omeprazole can be found in the omeprazole package insert, Adverse Reactions section.

• Esomeprazole is extensively metabolized in the liver by CYP2C19 and CYP3A4.
• In vitro and in vivo studies have shown that esomeprazole is not likely to inhibit CYPs 1A2, 2A6, 2C9, 2D6, 2E1 and 3A4. No clinically relevant interactions with drugs metabolized by these CYP enzymes would be expected.
• Drug interaction studies have shown that esomeprazole does not have any clinically significant interactions with phenytoin, warfarin, quinidine, clarithromycin or amoxicillin.
• Post-marketing reports of changes in prothrombin measures have been received among patients on concomitant warfarin and esomeprazole therapy. Increases in INR and prothrombin time may lead to abnormal bleeding and even death.
• Patients treated with proton pump inhibitors and warfarin concomitantly may need to be monitored for increases in INR and prothrombin time.
• Esomeprazole may potentially interfere with CYP2C19, the major esomeprazole metabolizing enzyme.
• Co-administration of esomeprazole 30 mg and diazepam, a CYP2C19 substrate, resulted in a 45% decrease in clearance of diazepam. Increased plasma levels of diazepam were observed 12 hours after dosing and onwards.
• However, at that time, the plasma levels of diazepam were below the therapeutic interval, and thus this interaction is unlikely to be of clinical relevance.
• Clopidogrel is metabolized to its active metabolite in part by CYP2C19.
• Concomitant use of esomeprazole 40 mg results in reduced plasma concentrations of the active metabolite of clopidogrel and a reduction in platelet inhibition. Avoid concomitant administration of Nexium I.V. with clopidogrel.
• When using Nexium I.V., consider use of alternative anti-platelet therapy.
• Omeprazole acts as an inhibitor of CYP2C19. Omeprazole, given in doses of 40 mg daily for one week to 20 healthy subjects in cross-over study, increased Cmax and AUC of cilostazol by 18% and 26%, respectively.
• Cmax and AUC of one of its active metabolites, 3,4-dihydro-cilostazol, which has 4-7 times the activity of cilostazol, were increased by 29% and 69%, respectively.
• Co-administration of cilostazol with esomeprazole is expected to increase concentrations of cilostazol and its above mentioned active metabolite. Therefore, a dose reduction of cilostazol from 100 mg twice daily to 50 mg twice daily should be considered.
• Concomitant administration of esomeprazole and a combined inhibitor of CYP2C19 and CYP3A4, such as voriconazole, may result in more than doubling of the esomeprazole exposure. Dose adjustment of esomeprazole is not normally required for the recommended doses. However, in patients who may require higher doses, dose adjustment may be considered.
• Drugs known to induce CYP2C19 or CYP3A4 (such as rifampin) may lead to decreased esomeprazole serum levels. Omeprazole, of which esomeprazole is an enantiomer, has been reported to interact with St. John's Wort, an inducer of CYP3A4. In a cross-over study in 12 healthy male subjects, St. John's Wort (300 mg three times daily for 14 days) significantly decreased the systemic exposure of omeprazole in CYP2C19 poor metabolizers (Cmax and AUC decreased by 37.5% and 37.9%, respectively) and extensive metabolizers (Cmax and AUC decreased by 49.6% and 43.9%, respectively). Avoid concomitant use of St. John's Wort or rifampin with Nexium.
• Co-administration of oral contraceptives, diazepam, phenytoin, or quinidine did not seem to change the pharmacokinetic profile of esomeprazole.
• Concomitant use of atazanavir and proton pump inhibitors is not recommended. Co-administration of atazanavir with proton pump inhibitors is expected to substantially decrease atazanavir plasma concentrations and thereby reduce its therapeutic effect.
• Omeprazole has been reported to interact with some antiretroviral drugs.
• The clinical importance and the mechanisms behind these interactions are not always known. Increased gastric pH during omeprazole treatment may change the absorption of the antiretroviral drug. Other possible interaction mechanisms are via CYP2C19.
• For some antiretroviral drugs, such as atazanavir and nelfinavir, decreased serum levels have been reported when given together with omeprazole.
• Following multiple doses of nelfinavir (1250 mg, twice daily) and omeprazole (40 mg daily), AUC was decreased by 36% and 92%, Cmax by 37% and 89% and Cmin by 39% and 75%, respectively, for nelfinavir and M8.
• Following multiple doses of atazanavir (400 mg daily) and omeprazole (40 mg daily, 2 hr before atazanavir), AUC was decreased by 94%, Cmax by 96%, and Cmin by 95%.
• Concomitant administration with omeprazole and drugs such as atazanavir and nelfinavir is therefore not recommended.
• For other antiretroviral drugs, such as saquinavir, elevated serum levels have been reported with an increase in AUC by 82%, in Cmax by 75% and in Cmin by 106% following multiple dosing of saquinavir/ritonavir (1000/100 mg) twice daily for 15 days with omeprazole 40 mg daily co-administered days 11 to 15.
• Dose reduction of saquinavir should be considered from the safety perspective for individual patients. There are also some antiretroviral drugs of which unchanged serum levels have been reported when given with omeprazole.
• Studies evaluating concomitant administration of esomeprazole and either naproxen (non-selective NSAID) or rofecoxib (COX-2 selective NSAID) did not identify any clinically relevant changes in the pharmacokinetic profiles of esomeprazole or these NSAIDs.
• Due to its effects on gastric acid secretion, esomeprazole can reduce the absorption of drugs where gastric pH is an important determinant of their bioavailability.
• Like with other drugs that decrease the intragastric acidity, the absorption of drugs such as ketoconazole, atazanavir, iron salts, erlotinib, and mycophenolate mofetil (MMF) can decrease, while the absorption of drugs such as digoxin can increase during treatment with esomeprazole. Esomeprazole is an enantiomer of omeprazole.
• Concomitant treatment with omeprazole (20 mg daily) and digoxin in healthy subjects increased the bioavailability of digoxin by 10% (30% in two subjects).
• Co-administration of digoxin with Nexium I.V. is expected to increase the systemic exposure of digoxin. Therefore, patients may need to be monitored when digoxin is taken concomitantly with Nexium I.V.
• Co-administration of omeprazole in healthy subjects and in transplant patients receiving MMF has been reported to reduce the exposure to the active metabolite, mycophenolic acid (MPA), possibly due to a decrease in MMF solubility at an increased gastric pH.
• The clinical relevance of reduced MPA exposure on organ rejection has not been established in transplant patients receiving Nexium I.V. and MMF.
• Use Nexium I.V. with caution in transplant patients receiving MMF.

Interactions With Investigations Of Neuroendocrine Tumors

• Drug-induced decrease in gastric acidity results in enterochromaffin-like cell hyperplasia and increased Chromogranin A levels which may interfere with investigations for neuroendocrine tumors.

Tacrolimus

• Concomitant administration of esomeprazole and tacrolimus may increase the serum levels of tacrolimus.

Methotrexate

• Case reports, published population pharmacokinetic studies, and retrospective analyses suggest that concomitant administration of PPIs and methotrexate (primarily at high dose; see methotrexate prescribing information) may elevate and prolong serum levels of methotrexate and/or its metabolite hydroxymethotrexate. However, no formal drug interaction studies of methotrexate with PPIs have been conducted.