(This description is for one drug and similar for other drugs) We repacked the placebo, lansoprazole 15 mg and lansoprazole 15 mg plus domperidone 10 mg in 180 envelopes (times two) and then two envelope in one envelope each for evening and morning of the same size, shape and color and their name were changed as drug one, drug two and drug three by a person who was not taking part in the study to the patients (single-blind) and investigators (double-blind) blinded of it. The group assign paper was sealed in another envelope that was opened to know which drug corresponds to either drug one or drug two or drug three after the statistical analysis(triple-blind).