Mikromol featured product: omeprazole

Featured product

Omeprazole

API and impurity reference standards

Introduction

Omeprazole (also known as Losec, Prilosec, Losec MUPS, and Pyrocalm) is a medicine used to treat indigestion, heartburn and acid reflux. It also treats peptic ulcer disease, upper gastrointestinal bleeding, and Zollinger-Ellison syndrome - a disease in which tumours cause acid overproduction in the stomach. The medicine is taken as a capsule, tablet or suspension, or by injection into a vein, and is available both over the counter and on prescription. In 1988, omeprazole became the first of a class of compounds developed in 1960s Sweden and known as proton pump inhibitors (PPIs) to pass clinical trials. It is a powerful inhibitor, with relatively few and mild side effects (such as headaches, diarrhoea and stomach pain). Due to their good safety profile, several PPIs are available over the counter without a prescription, and they are widely used in North America. Astra Zeneca was the first company to release omeprazole and, when its patent ran out in 2001, it produced a new drug, esomeprazole, sold under the brand name Nexium. Omeprazole is chiral, and a racemic mixture of the (R)- and (S)-enantiomer, while esomeprazole is purely the (S)-enantiomer. It is less easily metabolised in the body - and so maintains a higher plasma drug concentration for longer, making it the more suitable choice of the two.

Mechanism of action

Proton pumps are membrane proteins responsible for building up proton gradients across a biological membrane. The proton pump responsible for stomach acid production is ATP-driven, and known as the hydrogen/potassium adenosine triphosphate enzyme system (H⁺,K⁺-ATPase). Found in the secretory surface of acid-producing parietal cells, it transports H⁺ ions into the stomach in exchange for K⁺ ions. Omeprazole is able to bind to a thiol group on the H⁺,K⁺-ATPase, irreversibly inhibiting the secretion of acid. As enantiomers, both omeprazole and esomeprazole have the same  degradation impurities, including N-oxide and S-oxide compounds.

LGC Mikromol manufactures a number of high-quality API and impurity reference standards for both omeprazole and esomeprazole. We invite you to browse the table below to find out more about our range.