Cimetidine and ranitidine both block histamine 2 receptors in the stomach to limit the production of acid. They both work in the same way and are approved for many of the same conditions, but there are some subtle differences that can be important for patients choosing between them. Ranitidine is stronger and can be prescribed to a wider array of patients, for example. People considering options for medications to manage stomach acid may want to talk about the various medications available with their doctors before choosing one.
Stomach ulcers, gastrointestinal reflux disease (GERD), and disorders involving hypersecretion of stomach acid can all be treated with cimetidine and ranitidine. The medication must be taken on a regular basis to be effective, as the levels need to remain stable to control the production of acid in the stomach. If patients miss a dose, they can make it up, unless they are close to the time of the next dose. It may also help to make dietary changes to eliminate acidic foods that might exacerbate stomach irritation.
An important difference between cimetidine and ranitidine is that cimetidine is more likely to cause adverse drug interactions. If a patient needs to take other medications, such reactions can be a cause for concern, and it may be advisable to go with the drug that is associated with fewer complications. People with disorders related to overproduction of stomach acid could also have other health issues that require management, making it important to balance treatments to avoid conflicts.
Ranitidine is approved for use in children, in contrast with cimetidine, which can be another important difference. In addition, this more potent medication can reduce the risk of recurrence after a stomach ulcer resolves. This added protection may lead a doctor to recommend the medication when a patient requires treatment for ulcers. These differences can impact prescribing decisions when a doctor reviews a patient's case to decide which medication would be suitable.
Patients may be able to access cimetidine and ranitidine over the counter, at least in some formulations. Regional laws vary, and the medications are available in a variety of formats around the world. Doctors may recommend drugstore versions first, to allow the patient to try the medication before buying a prescription. If a suitable formulation is not available without a prescription, patients may be able to try samples to determine if the medication will meet their needs.