Ranitidine comes as a tablet, an effervescent tablet, effervescent granules, and a syrup to take by mouth. It is usually taken once a day at bedtime or two to four times a day. For GERD Rantac or zantac both should be rated world no.1 medicine because every time I use it works and gives quick relief all stomach related problem. You should contact your doctor for clarification. Zantac (ranitidine) belongs to a group of drugs called histamine-2 blockers. Ranitidine works by reducing the amount of acid your stomach produces. ZANTAC® (ranitidine hydrochloride) Injection. ZANTAC® (ranitidine hydrochloride) Injection Premixed. DESCRIPTION. The active ingredient in ZANTAC Injection and ZANTAC Injection Premixed is ranitidine hydrochloride (HCl), a histamine H2-receptor antagonist. Find the answers to frequently asked questions on ZantacOTC.com including the differences between H2 blockers and PPIs. Dr. Considine responded: Yes. However, the next question should be why should you need to do that. If you need something like gas-x or beano you might want to see if you have a food intolerance or allergy. What is the active ingredient in Zantac 75 ®? The active ingredient is ranitidine. What time of day should I take Zantac 75 ®? Zantac 75 ® can be taken 30 to 60 minutes before eating food or drinking beverages that cause heartburn to prevent symptoms, or it can be taken when heartburn symptoms strike, providing relief in as little as 30. How to use Zantac. Take this medication by mouth with or without food as directed by your doctor, usually once or twice daily. It may be prescribed 4 times a day for some conditions. Information on the drug ranitidine (Zantac) used in promoting healing of stomach and duodenal ulcers, heartburn, esophagitis, and Zollinger Ellison Syndrome. Side effects, drug interactions, and dosing information is provided. If you take Zantac for stomach ulcers, it might take up to eight weeks before an ulcer heals. You should keep using the medication as your doctor prescribes and tell your doctor if your symptoms.