Dexlansoprazole

Introduction Overview

Generic Name

dexlansoprazole

Brand Name

Dexilant

Dosage Form

oral delayed-release capsule

Drug Class

Proton pump inhibitors (PPIs)

Pharmacokinetics

Absorption:
Dexlansoprazole is administered orally as a dual delayed-release capsule designed to enhance and prolong plasma concentrations over a 24-hour period. Upon ingestion, the dual delayed-release formulation allows for two separate releases of the drug in the gastrointestinal tract: an initial release in the proximal small intestine and a delayed release in the distal small intestine. This staged absorption results in prolonged plasma concentration peaks, allowing once-daily dosing. Bioavailability is high and not significantly altered by food intake; patients may take Dexilant with or without meals. Peak plasma concentrations are typically reached between 1 to 2 hours and again between 4 to 5 hours after dosing due to the biphasic release.

Distribution:
Dexlansoprazole exhibits moderate plasma protein binding, approximately 97%, predominantly to albumin. The drug is distributed systemically, reaching the parietal cells in the gastric mucosa where it exerts its therapeutic effect. The volume of distribution is moderate, suggesting that the drug is largely confined to plasma and extracellular fluids. It does not significantly accumulate in adipose tissue. Dexlansoprazole crosses the placental barrier and is present in breast milk; therefore, caution is recommended during pregnancy and breastfeeding.

Metabolism:
Dexlansoprazole is extensively metabolized in the liver primarily via the cytochrome P450 enzyme system, mainly CYP2C19 and to a lesser extent CYP3A4. The drug undergoes demethylation and sulfoxide reduction to inactive metabolites. Genetic polymorphisms in CYP2C19 can impact metabolism rate, with poor metabolizers achieving higher plasma concentrations, possibly influencing efficacy and safety. However, the dual delayed-release formulation provides sustained drug levels regardless of metabolic variability, enhancing therapeutic consistency.

Elimination:
The metabolites of dexlansoprazole are primarily excreted renally, with approximately 51% eliminated via the urine and about 45% via feces. The elimination half-life averages 1 to 2 hours but pharmacodynamic effects last much longer due to irreversible binding to the gastric H+/K+ ATPase proton pump. Renal impairment does not necessitate dose adjustment, but use in severe hepatic impairment requires caution due to metabolism reliance on the liver. The drug’s elimination and systemic exposure have been well characterized in healthy and patient populations, supporting once-daily dosing regimens.

Dosage Forms

Available Dosage Forms:
- Oral delayed-release capsules containing dexlansoprazole at strengths of 30 mg and 60 mg.
- Kapidex is another brand name formulation available as oral delayed-release capsules.
- Dexilant SoluTab: an orally disintegrating tablet formulation available for patients who have difficulty swallowing capsules.

Dosages for Adults and Adolescents:
- Healing of erosive esophagitis and maintenance of healed erosive esophagitis: 30 mg once daily.
- Treatment of symptomatic gastroesophageal reflux disease (GERD): 30 mg once daily.
- For patients not responding satisfactorily to once-daily dosing, 60 mg once daily may be considered.
- Duration of therapy: up to 6 months for erosive esophagitis; dosing duration depends on clinical response.

Specific Patient Populations:
- Adolescents aged 12 through 17 years: indicated for healing of erosive esophagitis and relief of heartburn symptoms, with similar dosing regimens as adults (30 mg once daily).
- Pediatric patients below 12 years: safety and efficacy not established; use not recommended.
- No dosage adjustments are usually required in elderly patients or those with mild to moderate renal impairment.
- Use with caution and under medical supervision in patients with severe hepatic impairment due to altered metabolism.

Clinical Guidelines:
- Capsules should be swallowed whole; however, if unable to swallow, the capsule can be opened and granules sprinkled on applesauce and immediately ingested without chewing.
- Can be taken with or without food as absorption is not significantly affected by food intake.
- Adherence to prescribed dosing schedule is critical for efficacy and to ensure adequate acid suppression.

Mechanism Of Action

Dexlansoprazole is a proton pump inhibitor (PPI) that suppresses gastric acid secretion by specifically targeting and inhibiting the hydrogen-potassium adenosine triphosphatase enzyme system—commonly known as the gastric proton pump—located on the secretory surface of gastric parietal cells. This enzyme system is responsible for the final step in the production and secretion of hydrochloric acid in the stomach.

Upon oral administration, dexlansoprazole is absorbed into the systemic circulation and is activated in the acidic environment of the parietal cell canaliculi. The active form covalently binds to cysteine residues on the proton pump, leading to irreversible inhibition of the enzyme's activity. This results in profound and prolonged suppression of gastric acid secretion regardless of the stimulus for acid secretion, effectively reducing intragastric acidity.

Unlike some other PPIs, Dexilant’s dual delayed-release formulation allows for two separate releases of the active drug at different times after ingestion, resulting in extended acid suppression over 24 hours. This biphasic release minimizes variability in acid control and enhances symptom relief with once-daily dosing.

Clinically, this mechanism reduces gastroesophageal reflux symptoms and facilitates healing of erosive esophagitis by restoring the integrity of the esophageal mucosa. Additionally, prolonged acid suppression reduces complications associated with GERD such as Barrett's esophagus. Compared to other PPIs, dexlansoprazole provides enhanced pharmacokinetic profiles due to its dual delayed-release design, resulting in sustained plasma drug levels and improved therapeutic outcomes supported by clinical trials.

Pharmacological Actions

Potent inhibition of gastric H+/K+ ATPase proton pump leading to sustained suppression of gastric acid secretion.
Administration results in a biphasic plasma concentration profile due to dual delayed-release technology, providing prolonged acid suppression.
Reduction of gastric acidity promotes healing of erosive esophagitis and reduces GERD-associated symptoms such as heartburn and regurgitation.
Exhibits high plasma protein binding (~97%) contributing to a controlled systemic exposure.
Metabolized primarily via CYP2C19 and CYP3A4 hepatic enzymes into inactive metabolites.
Helps in maintenance therapy to prevent relapse of erosive esophagitis and GERD symptoms over extended periods.
Demonstrates efficacy in symptom relief in adolescents aged 12 years and older, with similar pharmacodynamic profiles as adults.
Minimal interaction with food on pharmacokinetics allows flexible dosing with or without meals.
Compared to other PPIs, its dual-release formula enhances pharmacokinetic profiles, sustaining plasma concentrations longer.
By reducing acid secretion, indirectly reduces pepsin activity and gastric mucosal irritation.
Prolonged acid suppression may increase gastric pH, potentially affecting absorption of certain drugs that require acidic environment.
Irreversible binding to proton pump ensures effect lasting beyond the plasma half-life of the drug.
Supports repair of esophageal mucosal damage by reducing acid exposure.
May reduce symptoms and complications related to GERD and erosive esophagitis such as dysphagia and esophageal strictures.
Exerts no significant anticholinergic or H2 receptor blocking effects.

Therapeutic Or Clinical Uses

Treatment of symptomatic gastroesophageal reflux disease (GERD) to relieve heartburn and acid reflux symptoms.
Healing of erosive esophagitis caused by gastric acid damage in adults and adolescents aged 12 years and older.
Maintenance therapy for healed erosive esophagitis to prevent relapse and recurrence of symptoms.
Management of GERD-related complications, including prevention of esophageal strictures due to acid-induced injury.
Treatment of upper gastrointestinal conditions characterized by excessive gastric acid secretion.
Off-label use in managing nonerosive reflux disease (NERD) symptoms under clinical discretion.
Potential reduction in the risk of Barrett’s esophagus progression by suppressing gastric acid and reflux.
Symptomatic relief in patients with frequent heartburn where acid suppression improves quality of life.
Adjunctive therapy in eradication regimens for Helicobacter pylori infection, when used with antibiotics (though not the primary indication).
Use in patients unable to tolerate other proton pump inhibitors due to its unique pharmacokinetic profile.
Elimination or reduction of nighttime acid breakthrough due to prolonged duration of effect from dual delayed release.
Suitable for long-term management of GERD symptoms to avoid complications associated with uncontrolled acid reflux.
Reduction of acid-related damage and irritation to esophageal mucosa allowing improved mucosal healing.
Treatment regimen flexibility due to ability to take with or without food enhances patient adherence.
Off-label use in conditions with pathologic gastric acid hypersecretion as determined by clinician.

Side Or Adverse Effects

Common gastrointestinal symptoms including nausea, vomiting, abdominal pain, and gas.
Diarrhea, which can be mild but may signify Clostridium difficile infection in some cases.
Headache frequently reported during therapy with proton pump inhibitors including Dexilant.
Mouth pain and sore throat may occur due to upper respiratory tract irritation.
Upper respiratory symptoms including stuffy nose, sinus pain, and cold-like symptoms.
Serious adverse events: severe stomach pain and watery or bloody diarrhea indicating possible serious infection.
Seizures and convulsions have been reported rarely; requires immediate medical attention.
Musculoskeletal symptoms like sudden joint pain or trouble moving a bone (hip, wrist, back) possibly due to fractures.
Risk of kidney problems manifesting as fever, rash, decreased urination, and blood in urine signaling acute interstitial nephritis.
Hypomagnesemia characterized by dizziness, tremors, irregular or fast heartbeat, muscle cramps or spasms.
Potential development of fundic gland polyps in stomach with long-term use.
Vitamin B12 deficiency possible after prolonged use over 3 years, necessitating monitoring and management.
New onset or worsening symptoms of lupus, including joint pain and photosensitive skin rash on cheeks or arms.
Increased risk of bone fractures (hip, wrist, spine) with long-term use or high-dose therapy.
Allergic reactions ranging from mild rash to severe anaphylaxis including swelling of face, lips, tongue, or throat.

Precautions

Use cautiously in patients with history of severe liver disease due to hepatic metabolism dependency.
Monitor magnesium levels during prolonged therapy as hypomagnesemia can develop and cause serious complications.
Patients with osteoporosis or low bone mineral density should be evaluated prior to long-term treatment.
Avoid use in patients allergic to dexlansoprazole or any component of the formulation.
Special caution if history of kidney impairment or symptoms suggestive of kidney problems.
Pregnancy: avoid unless clearly needed; potential fetal risk requires effective contraception during treatment.
Breastfeeding women should consult healthcare providers due to potential excretion into breast milk.
Not approved for use in children under 12 years; efficacy and safety have not been established.
Inform healthcare providers of all medications taken to avoid potential drug interactions.
Avoid concomitant use with rilpivirine-containing antiretroviral agents such as Complera, Edurant, or Odefsey due to reduced rilpivirine effectiveness.
Discontinue if signs of allergic reactions or serious adverse effects occur and seek medical attention immediately.
Long-term PPI use may require regular monitoring for B12 deficiency and bone health assessments.
Patients should report persistent diarrhea, abdominal pain, or unusual symptoms promptly.
Use lowest effective dose and shortest duration needed to minimize risks of complications.
Ensure patients understand proper administration techniques, including not crushing or chewing capsules.

Warnings

Serious kidney problems can occur; promptly report symptoms such as decreased urination, blood in urine, fever, rash, or joint pain.
Severe diarrhea, especially if watery or bloody, could indicate Clostridium difficile infection; seek urgent medical care.
Possible development or exacerbation of lupus erythematosus, with characteristic joint pain and photosensitive rash.
Increased risk of bone fractures of hip, wrist, or spine particularly with long-term use or doses exceeding once daily.
Heartburn symptoms can mimic myocardial infarction; patients should seek emergency care if chest pain radiates to jaw or shoulder with associated symptoms.
Use in pregnancy may cause fetal harm; effective contraception recommended during treatment.
May cause hypomagnesemia with symptoms such as irregular heartbeat, tremors, muscle spasms, requiring prompt correction.
Potential false positives or altered results in drug-screening urine tests; inform laboratory personnel about Dexilant use.
Long-term use associated with gastric fundic gland polyps; discuss risks versus benefits with healthcare provider.
Not intended for pediatric patients under 12 years due to unknown safety and efficacy.
Avoid concomitant use with rilpivirine as acid suppression can reduce antiviral efficacy and lead to resistance.
Caution in patients with severe hepatic impairment due to altered drug metabolism and increased plasma concentrations.
Patients should not suddenly discontinue without medical advice to avoid rebound acid hypersecretion.
Risk of allergic reactions including anaphylaxis necessitates immediate discontinuation if symptoms develop.
May interfere with results of medical tests; inform healthcare professionals prior to testing.

Contraindication

Hypersensitivity to dexlansoprazole or any proton pump inhibitor component.
History of severe allergic or anaphylactic reaction to Dexilant or related PPIs.
Concurrent use with rilpivirine-containing medications (e.g., Complera, Edurant, Odefsey) due to significant drug interaction.
Previous history of kidney problems directly attributed to Dexilant or related PPI therapy.
Patients with unexplained persistent gastrointestinal symptoms until evaluation rules out malignancy, as treatment may mask symptoms.
Children under 12 years of age due to lack of safety and efficacy data.
Severe hepatic impairment in some cases where benefit-risk ratio is unfavorable without specialist supervision.
Known hypersensitivity or intolerance to any excipients in the Dexilant capsule formulation.
Active gastrointestinal bleeding or ulceration requiring alternative medical treatment in acute phase.
Patients who have had severe respiratory complications linked to prior PPI use.
Co-administration with drugs with narrow therapeutic indices metabolized through CYP450 pathways without medication adjustments.

Drug Interactions

Rilpivirine-containing antiretrovirals (Complera, Edurant, Odefsey) - acid suppression decreases rilpivirine absorption and effectiveness; contraindicated.
Methotrexate - co-administration may increase methotrexate levels leading to toxicity; close monitoring recommended.
Rifampin - induces CYP enzymes possibly decreasing dexlansoprazole effectiveness; dosage adjustment may be necessary.
St. John’s wort - induces CYP450 enzymes, potentially reducing dexlansoprazole plasma concentration and efficacy.
Warfarin and other anticoagulants - possible interaction altering coagulation parameters; monitor INR closely.
Drugs requiring acidic gastric environment for absorption (e.g., ketoconazole, atazanavir) may have reduced bioavailability.
Clopidogrel - metabolism via CYP2C19 may be competitively inhibited, potentially reducing clopidogrel activation.
Digoxin - acid suppression may alter absorption; monitor digoxin levels to avoid toxicity.
Diazepam and phenytoin - may be affected by altered CYP metabolism; dosage adjustments may be necessary.
Iron salts - decreased absorption with elevated gastric pH; separate administration times recommended.
Calcium carbonate - absorption may be affected; consider timing of dosing.
Other PPIs or H2 blockers - combination may increase risk of adverse effects without added benefit.
Cilostazol - possible increased levels due to enzyme inhibition; clinical monitoring advised.
Theophylline - increased plasma levels reported; monitor for toxicity.
Mycophenolate mofetil - interaction might reduce active metabolite levels; careful monitoring indicated.

Preparations Of The Drug

Dexilant 30 mg oral delayed-release capsules containing dexlansoprazole as active ingredient.
Dexilant 60 mg oral delayed-release capsules for higher dose requirements.
Kapidex 30 mg and 60 mg brand formulations of dexlansoprazole identical in composition and use.
Dexilant SoluTab orally disintegrating tablets for patients with swallowing difficulties.
Capsules consist of enteric-coated granules to facilitate biphasic delayed release in the gastrointestinal tract.
Available in blister packs or bottles for retail and institutional dispensing.
Contains inactive ingredients such as hypromellose, hydroxypropyl cellulose, magnesium stearate, and methacrylic acid polymers for delayed-release properties.
Typically supplied in packets containing 7, 14, 28, or 30 capsules depending on regulatory region and manufacturer.
Packaged with patient medication guides detailing administration instructions and safety information.
Provided with professional prescribing information sheets outlining indications, contraindications, and clinical guidance.
Manufactured under strict Good Manufacturing Practice (GMP) guidelines ensuring formulation stability and quality.
Stored at controlled room temperature away from moisture and heat to maintain product integrity.
No injectable or intravenous forms currently available; exclusively oral formulations.
Not currently available as generic in all countries; generic versions generally contain same formulation if approved.
Available in multiple global markets with specific labeling adhering to regional regulatory authorities.