Aciphex 20 mg Tablets

Brand Name

The medication is marketed under the brand name Aciphex, a widely recognized label in the field of gastrointestinal disorder management.

International Nonproprietary Name (INN)

The active ingredient in this product is identified globally as rabeprazole, a name standardized for consistency across international pharmacological practices.

Form of Release

Aciphex is available as delayed-release oral tablets, designed to protect the active substance from stomach acid. These tablets come in strengths of 10 mg and 20 mg, typically packaged in blister packs or bottles to ensure proper dosing and storage.

Composition

Each delayed-release tablet of Aciphex contains rabeprazole sodium as the primary active substance, with dosages of 10 mg or 20 mg (equivalent to rabeprazole base). The formulation includes several inactive ingredients, such as mannitol, which acts as a filler, and magnesium oxide, providing a stabilizing effect. Additional excipients like hydroxypropyl cellulose serve as binders, while the enteric coating comprises methacrylic acid copolymer, ethyl acrylate, and triethyl citrate to ensure release in the intestine. Trace stabilizers maintain the drug’s integrity, supporting consistent efficacy throughout its shelf life.

Pharmacologic Properties

Pharmacodynamics

Aciphex belongs to the proton pump inhibitor (PPI) class, exerting its effects by irreversibly blocking the hydrogen/potassium adenosine triphosphatase (H+/K+ ATPase) enzyme system in gastric parietal cells. This inhibition suppresses gastric acid secretion, reducing both basal and stimulated acid output, which elevates intragastric pH and promotes healing in acid-related conditions. Its action targets the final step of acid production, offering prolonged suppression compared to H2-receptor antagonists, with effects lasting up to 24 hours per dose.

The medication also exhibits antibacterial activity against Helicobacter pylori when combined with antibiotics, aiding eradication in peptic ulcer disease. Clinical studies demonstrate its ability to heal erosive esophagitis in 85–90% of patients within 4–8 weeks, while maintaining symptom relief in maintenance therapy. It does not alter gastric motility or hormone secretion significantly, focusing solely on acid control. This targeted mechanism underpins its efficacy in managing acid-mediated gastrointestinal disorders effectively.

Pharmacokinetics

Following oral administration, Aciphex is absorbed in the small intestine due to its enteric coating, with peak plasma concentrations reached within 2 to 5 hours. Bioavailability is approximately 52%, reduced by first-pass metabolism, and food delays absorption slightly without affecting overall uptake. The drug binds to plasma proteins at about 96%, distributing primarily to the bloodstream and gastric mucosa.

Metabolism occurs extensively in the liver via cytochrome P450 enzymes CYP2C19 and CYP3A4, converting rabeprazole into inactive thioether, sulfone, and desmethyl metabolites. The half-life ranges from 1 to 2 hours, though its antisecretory effect persists longer due to irreversible enzyme binding. Elimination is predominantly urinary, with 90% excreted as metabolites and less than 10% via feces, reflecting minimal biliary clearance. This rapid metabolism ensures low systemic accumulation with once-daily dosing.

Indications for Use

Aciphex is prescribed for the treatment of erosive or ulcerative gastroesophageal reflux disease (GERD) in adults, where it heals esophageal damage and relieves symptoms like heartburn. It is also indicated for maintenance therapy in healed GERD to prevent relapse, offering long-term acid control. The medication treats symptomatic GERD without erosions, addressing persistent reflux discomfort.

In combination with amoxicillin and clarithromycin, it eradicates Helicobacter pylori in patients with peptic ulcer disease, promoting ulcer healing and reducing recurrence. It manages Zollinger-Ellison syndrome and other hypersecretory conditions by controlling excessive acid production. These applications highlight its role as a versatile PPI in acid-related gastrointestinal care.

Contraindications

Aciphex is contraindicated in patients with known hypersensitivity to rabeprazole, substituted benzimidazoles, or any tablet component, such as mannitol, where reactions could range from rash to anaphylaxis. It is also prohibited in those requiring immediate acid suppression, as its delayed-release nature delays onset compared to intravenous options.

Use with rilpivirine-containing products is restricted due to reduced antiviral efficacy from increased gastric pH. Severe liver disease does not strictly contraindicate it, but caution is warranted. The medication should not be used in patients with a history of severe PPI-related adverse events, such as interstitial nephritis, unless benefits outweigh risks. Pregnancy and breastfeeding contexts limit its use unless clearly necessary, given limited safety data.

Method of Administration and Dosage

Administration Guidelines

The tablets should be taken orally, swallowed whole with water, typically 30 minutes before a meal to optimize acid suppression timing. They should not be chewed, crushed, or split, as this disrupts the enteric coating and reduces efficacy. Morning administration is preferred, though flexibility exists for patient convenience.

Dosage for Adults and Children

For adults with erosive GERD, the typical dose of Aciphex is 20 mg once daily for 4–8 weeks, extendable if healing is incomplete. Maintenance therapy uses 20 mg daily, reducible to 10 mg for milder cases. Symptomatic GERD requires 20 mg daily for 4 weeks, with reassessment if symptoms persist. Helicobacter pylori eradication involves 20 mg twice daily with antibiotics for 7 days. Zollinger-Ellison syndrome starts at 60 mg daily, adjustable up to 120 mg in divided doses. Children under 12 are not prescribed this therapy, while those 12–17 with GERD use 20 mg daily for up to 8 weeks.

Dose Adjustment in Specific Conditions

No adjustment is needed for renal impairment, as excretion is primarily metabolic. Mild to moderate liver dysfunction allows standard dosing, but severe cases require caution and possible reduction due to altered metabolism. Elderly patients or those with mild symptoms may start at 10 mg daily, guided by response. Treatment duration and dose should align with clinical improvement, avoiding unnecessary prolongation.

Side Effects

Aciphex may cause a range of side effects, though many patients experience only mild reactions with short-term use. Common issues include headache, diarrhea, or abdominal pain, often resolving without intervention. Nausea, flatulence, or constipation are also reported, typically transient as the body adjusts.

Less frequent effects include rash, dizziness, or fatigue, reflecting systemic exposure. Rare but serious reactions, such as hypomagnesemia, vitamin B12 deficiency, or Clostridium difficile-associated diarrhea, may occur with prolonged use, warranting monitoring. Acute interstitial nephritis or severe cutaneous reactions (e.g., Stevens-Johnson syndrome) require immediate cessation and medical attention. Regular follow-ups help manage these risks, particularly in long-term therapy.

Overdose

Symptoms of Overdose

Excessive intake of Aciphex is unlikely to cause acute toxicity due to its wide therapeutic index, with symptoms limited to amplified side effects like headache, drowsiness, or gastrointestinal upset. Doses up to 240 mg daily have shown no consistent severe pattern, reflecting its metabolic clearance.

First Aid Measures

In case of overdose, medical consultation is advised, though emergency measures are rarely needed. No specific antidote exists, so treatment focuses on supportive care, such as hydration for diarrhea or rest for fatigue. Monitoring is recommended until symptoms subside, typically within 24 hours, given the drug’s short half-life.

Drug Interactions

Effects on Other Medications

Aciphex alters gastric pH, reducing absorption of pH-dependent drugs like ketoconazole or itraconazole, decreasing their efficacy. It inhibits CYP2C19, potentially increasing levels of diazepam, phenytoin, or warfarin, requiring dose adjustments or monitoring. Co-use with methotrexate may elevate toxicity risk, particularly at high doses, due to reduced clearance.

Drugs like clarithromycin, a CYP3A4 inhibitor, may increase rabeprazole levels, though this is rarely significant. Patients should report all medications to their healthcare provider to manage these interactions, especially in polypharmacy scenarios.

Compatibility with Alcohol and Food

Moderate alcohol use does not directly impair efficacy but may worsen GERD symptoms, suggesting limited intake during therapy. Food delays absorption slightly but enhances tolerability, making pre-meal dosing a practical strategy for optimizing effect and comfort.

Special Precautions

Use During Pregnancy and Breastfeeding

Aciphex is Category C in pregnancy, with animal studies showing no clear fetal harm but limited human data, reserved for cases where benefits outweigh risks. It may pass into breast milk in small amounts, so breastfeeding mothers should avoid it unless essential, with alternatives preferred to minimize infant exposure.

Women of childbearing age should confirm non-pregnant status before starting and use contraception during therapy to avoid unintended fetal exposure.

Impact on Driving and Operating Machinery

The medication may cause dizziness or drowsiness in some patients, suggesting caution with driving or machinery until tolerance is clear. Most individuals resume normal activities once adjusted, but initial use warrants observation for sedative effects.

Considerations for Elderly and Pediatric Populations

Elderly patients tolerate Aciphex well, with no significant efficacy differences, though monitoring for long-term effects like hypomagnesemia is key. Children aged 12–17 with GERD can use adult dosing, while those under 12 lack established safety data, limiting use to adolescents and adults.