Gasec 20mg is a proton pump inhibitor medication containing Omeprazole. Each pack contains 28 gastrocaps. This prescription medication is manufactured by Acino Switzerland and is used to reduce stomach acid production. Gasec contains Omeprazole 20mg as the active ingredient and comes in a pack of 28 gastrocaps. As a proton pump inhibitor, it works by reducing acid production in the stomach. This medication requires a prescription and should be taken as directed by your healthcare provider.