as previously said Konstantinos Stamatakis, in answer to a similar question:
Sulpiride is soluble in acidic solutions (0.1M HCl). Intraperitoneal tolerance for pH is about 4.5 so I suggest you make a solution of the drug then make it isotonic (0.9% NaCl) and check the pH. If the pH is not lower than 4.5 you can inject it. If not, you should adjust the pH a little, hoping the drug does not precipitate.