Background
The quest for medications against nausea and upset stomach is on-going in both human and veterinary medicine. In the past, antacids started as simple alkaline products that were swallowed to neutralize stomach acid. As the production of stomach acids came to be better understood, antacids that interfered with acid production were developed. The H2 blocking drugs were developed next. H2 blockers get their name because they block H2 receptors, which are receptors for histamine in the stomach that when stimulated would cause stomach acid production. Blocking the receptor meant blocking acid production. Cimetidine was the first H2 blocker released followed by ranitidine and famotidine. There are other receptors involved in stomach acid secretion stimulation besides H2 receptors however so even with H2 receptors blocked, acid could still be secreted.
Omeprazole represents a different tact: proton pump inhibition. The quantity of acid ultimately amounts to the quantity of protons. The proton pump is central to secreting acid into the stomach and with this pump inhibited, stomach acid production is halted. Proton pump inhibitors like omeprazole are the strongest antacids of all. It works not only when the stomach is full/digesting food but all the time.
How this Medication is Used
Omeprazole is used in the treatment of stomach ulcers or in the prevention of stomach ulcers. It is generally used once a day and may be given with or without food.
Side Effects
- Increases in liver enzymes may be induced by the use of omeprazole. This is not harmful but should be recognized as an omeprazole reaction should it be seen on a blood test.
- Omeprazole is able to reduce cerebrospinal fluid production though it is not known how.
- Ironically, nausea, vomiting, diarrhea and flatulence are occasionally reported as side effects.
Interactions with Other Drugs
- Omeprazole inhibits a system of liver enzymes called the cytochrome p450 system. Many other drugs depend on this system for removal. This means that if omeprazole is used, the following drugs will last longer and work stronger: diazepam/midazolam, phenytoin (used to treat both seizures and heart rhythm disturbances), and warfarin (a blood thinning agent).
- Because omeprazole reduces stomach acid, other drugs that require an acid environment for absorption into the body may not be as well absorbed. Such drugs include ketoconazole (an antifungal agent), and some forms of the antibiotic ampicillin.
- Blood levels of cyclosporine, an immunomodulator, may be increased with concurrent use of omeprazole.
- Clopidogrel, a blood thinner, may not be activated properly if used with omeprazole at the same time. It may be best to use a different antacid.
Concerns and Cautions
- Omeprazole should be stored at room temperature in a light-tight container (our pill vials or the original packaging).
- If your pet is reluctant to swallow the tablets/capsules, do not attempt to crush them as this will deactivate the medication. Please contact us if you are having difficulty giving your cat this medication.
- Omeprazole is removed from the body by both the liver and kidneys. The dosage of omeprazole may be altered if the patient suffers from either liver or kidney insufficiency. Please speak with us if your cat suffers from either of these conditions and you are concerned about the use of this medication.
- Safety of the use of this medication in lactation or pregnancy has not been established.
Please do not hesitate to get in touch if you have any concerns about giving your cat omeprazole.