The effective disintegration, dissolution and eventual absorption of 
dipyridamole in tablet or suspension form depends upon having a low pH in the stomach. Drugs that significantly raise the gastric pH are expected to reduce the bioavailability of 
dipyridamole tablets. This effect has been seen with 
famotidine. 
 The 
clinical significance of this interaction is unknown. Bear it in mind if an H2- 
receptor antagonist is given with 
dipyridamole. Note that modified-release preparations of 
dipyridamole (that are buffered) do not appear to be affected.