Dexlansoprazole

Oral
Erosive oesophagitis

Oral
Gastro-oesophageal reflux disease

Pharmacogenomics:

CYP2C19 is one of the major enzymes in the metabolism of dexlansoprazole. CYP2C19 polymorphism affects dexlansoprazole exposure.

FDA-approved drug label indicates that the exposure to dexlansoprazole is higher in CYP2C19 intermediate and poor metabolisers as compared to extensive metabolisers. No recommended dose adjustment.

Moderate (Child-Pugh class B): 30 mg once daily for up to 8 weeks. Severe (Child-Pugh class C): Not recommended.

May be taken with or without food. Swallow whole. Alternatively, cap may be opened & entire contents sprinkled in a tbsp of applesauce. Swallow immediately w/o chewing.

Concomitant use with rilpivirine.

Patient with risk factors for osteoporosis; reduced body stores or risk factors for vitamin B₁₂ malabsorption. Moderate to severe hepatic impairment. Children and elderly. Pregnancy and lactation. CYP2C19 poor metabolisers.

Significant: Clostridioides difficile-associated diarrhoea, osteoporosis-related bone fracture, vitamin B₁₂ deficiency, acute interstitial nephritis, subacute cutaneous and systemic lupus erythematosus, fundic gland polyps, hypersensitivity. Rarely, hypomagnesaemia.
Gastrointestinal disorders: Diarrhoea, abdominal pain, nausea, vomiting, flatulence.
Infections and infestations: Infection (e.g. Salmonella, Campylobacter).
Nervous system disorders: Headache.
Respiratory, thoracic and mediastinal disorders: Upper respiratory tract infection, nasopharyngitis.

PO: B

Monitor Mg levels prior to initiation of therapy and periodically thereafter (long-term treatments, or with risk for hypomagnesaemia).

Symptoms: Hypertension, hot flashes, contusion, oropharyngeal pain, weight loss. Management: Symptomatic and supportive treatment.

May decrease the serum concentration of atazanavir and nelfinavir. May increase the serum concentrations of methotrexate, tacrolimus and saquinavir. May reduce the absorption of pH-dependent drugs (e.g. ampicillin esters, ketoconazole, itraconazole, erlotinib, iron salts, dasatinib, nilotinib, mycophenolate mofetil).
Potentially Fatal: May decrease the serum concentration of rilpivirine.

Decreased exposure with St. John’s wort.

May increase serum chromogranin A (CgA) levels causing false-positive results in diagnostic test for neuroendocrine tumours. May cause hyper-response in gastrin secretion, falsely suggesting gastrinoma, with secretin stimulation test. May cause false-positive urine screening test for tetrahydrocannabinol (THC).

Description:
Mechanism of Action: Dexlansoprazole is the R-isomer of lansoprazole. It suppresses gastric acid secretion by inhibiting the H⁺/K⁺ ATPase at the secretory surface of the gastric parietal cell, thus blocking the final step in gastric acid production.
Pharmacokinetics:
Absorption: Food increases bioavailability. Time to peak plasma concentration: Initial peak: 1-2 hours; second peak: 4-5 hours.
Distribution: Volume of distribution: 40 L (symptomatic GERD). Plasma protein binding: 96-99%.
Metabolism: Extensively metabolised in the liver into inactive metabolites by CYP2C19 and CYP3A4 enzymes via hydroxylation and oxidation respectively; followed by formation of sulphate, glucuronide, and glutathione conjugates.
Excretion: Via urine (approx 51% as metabolites); faeces (approx 48%). Elimination half-life: Approx 1-2 hours.

Source: National Center for Biotechnology Information. PubChem Database. Dexlansoprazole, CID=9578005, https://pubchem.ncbi.nlm.nih.gov/compound/Dexlansoprazole (accessed on Mar. 24, 2020)

Store below 30°C.

Antacids, Antireflux Agents & Antiulcerants

A02BC06 - dexlansoprazole ; Belongs to the class of proton pump inhibitors. Used in the treatment of peptic ulcer and gastro-oesophageal reflux disease (GERD).

Annotation of FDA Label for Dexlansoprazole and CYP2C19. Pharmacogenomics Knowledgebase (PharmGKB). https://www.pharmgkb.org/. Accessed 13/12/2019.

Annotation of HCSC FDA Label for Dexlansoprazole and CYP2C19. Pharmacogenomics Knowledgebase (PharmGKB). https://www.pharmgkb.org/. Accessed 13/12/2019.

Annotation of Swissmedic Label for Dexlansoprazole and CYP2C19. Pharmacogenomics Knowledgebase (PharmGKB). https://www.pharmgkb.org/. Accessed 13/12/2019.

Anon. Dexlansoprazole. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 13/12/2019.

Buckingham R (ed). Dexlansoprazole. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 13/12/2019.

Dexilant Delayed Release Capsule 30, 60 mg (Takeda Malaysia Sdn Bhd). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my/. Accessed 03/02/2020.

Dexilant Delayed-Release Capsule (Takeda Pharmaceuticals America, Inc.). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 13/12/2019.