Article: Lansoprazole

Lansoprazole
Systematic (IUPAC) name
2-[(3-methyl-4-(2,2,2-trifluoroethoxy) pyridin-2-yl) methylsulfinyl] -1H-benzoimidazole
Identifiers
CAS number	103577-45-3
ATC code	A02BC03
PubChem	3883
DrugBank	APRD00077
Chemical data
Formula	C16H14F3N3OS
Mol. weight	369.363
Pharmacokinetic data
Bioavailability	80% or more
Metabolism	Hepatic
Half life	1 - 1.5 hours
Excretion	Renal Fecal
Therapeutic considerations
Pregnancy cat.	?
Legal status	?
Routes	Oral, I.V.

Prevacid Logo

Lansoprazole (lan-SOE-pra-zole) is a proton pump inhibitor which prevents the stomach from producing acid. It is marketed under the following brand names:

• Takepron® in Japan
• Prevacid® by TAP Pharmaceuticals in the U.S.
• Zoton®

Pharmacology

Lansoprazole is a proton pump inhibitor similar to omeprazole. Lansoprazole's plasma elimination half-life is not proportional to the duration of the drug's effects (i.e. gastric acid suppression). The plasma elimination half-life is 1.5 hours or less, and the effects of the drug last for over 24 hours after it has been given for 5 days or more.

Indications

Lansoprazole is indicated for:

• Treatment of ulcers of the stomach and duodenum, and NSAID-induced ulcers
• Treatment of gastroesophageal reflux disease (GERD) (also known as acid reflux disease)
• Treatment of Zollinger-Ellison Syndrome
• Treatment of Barrett's esophagus
• Adjunctive treatment of H. pylori infection, alongside antibiotics

Contraindications

• Absorption of lansoprazole is reduced by antacids.
• PPI’s reduce absorption of antifungals (itraconazole and ketoconazole) and possibly increase Digoxin in plasma
• Increases plasma conc of Cilostazol (risk of toxicity)
• Absorption of lansoprazole possibly reduced by:
  • sucralfate
  • ampicillin
  • bisacodyl
  • delavirdine
  • fluvoxamine
  • iron salts
  • theophylline
  • voriconazole

Side effects

• Infrequent: dry mouth, insomnia, drowsiness, blurred vision, rash, pruritus
• Rarely and very rarely: taste disturbance, liver dysfunction, peripheral oedema, hypersensitivity reactions (including bronchospasm, urinary, angioedema, anaphylaxis), photosensitivity, fever, sweating, depression, interstitial nephritis, blood disorders (including leukopenia, leukocytosis, pancytopenia, thrombocytopenia), arthralgia, myalgia, skin reactions (including Stevens-Johnson syndrome, toxic epidermal necrolysis, bullous eruption)
• Increases the risk of gastric-intestinal infections by reducing gastric acidity.
• Severe: Gastro-intestinal disturbances (such as nausea, vomiting, abdominal pain, flatulence, diarrhea, constipation), headache, dizziness