Nexium 40 mg is a prescription medication containing esomeprazole, manufactured by AstraZeneca. This package contains 14 tablets designed to reduce stomach acid production and treat various gastrointestinal conditions. Nexium (esomeprazole) belongs to a class of medications called proton pump inhibitors (PPIs). The 40 mg strength is typically prescribed for conditions requiring stronger acid suppression. As with all prescription medications, this should only be taken under the direction and supervision of a healthcare provider.