Functional dyspepsia is known to be caused by diverse pathogenetic factors. From a clinical viewpoint, acid-related symptoms, like acid regurgitation, heartburn, and epigastric pain (acid-type) can be differentiated from the general dysmotility-type dyspeptic symptoms, such as fullness and nausea/vomiting.

A study evaluated the effect of a 4-week treatment with ranitidine twice a day in 346 patients and an antacid in 340 patients, with acid-related functional dyspepsia, on the severity and course of symptoms.

• With ranitidine treatment, acid-related and general dyspeptic symptoms were relieved in a significantly higher proportion of patients after two and four weeks, compared with antacid treatment.
• Symptoms were completely relieved with ranitidine after two weeks of treatment in 37% and after four weeks in 66%, while with the antacid, complete resolution was seen in 13% and 30%, respectively (p < 0.005), after two and four weeks.
• Patients having severe symptoms, a history of ulcer and long-term dyspepsia and slight endoscopic changes in the upper gastrointestinal tract were found to have a significantly faster and more marked response.
• Both the treatments were well tolerated.

In acid-related functional dyspepsia, ranitidine appears to be a better drug compared to an antacid in relieving symptoms.

Source: Hotz J, Plein K, Bunke R. The effectiveness of ranitidine in non-ulcer dyspepsia (functional dyspepsia) in comparison with an antacid. Med Klin (Munich). 1994 Feb 15;89(2):73-80, 107.