Study to Examine the Effect of Coated Phenylephrine Suppositories on Anal Pressure in Healthy Subjects

• The primary efficacy parameter is change in Resting Anal Pressure from baseline. [ Time Frame: 8 hours ] [ Designated as safety issue: No ]
  

• The ratio of change in anal pressure to plasma Phenylephrine level. [ Time Frame: 8 hours ] [ Designated as safety issue: Yes ]
  
• The ratio of change in anal pressure to change in blood pressure. [ Time Frame: 8 hours ] [ Designated as safety issue: Yes ]
  
• The ratio of change in anal pressure to change in heart rate. [ Time Frame: 8 hours ] [ Designated as safety issue: Yes ]
  

This is an open label, dose-finding study. Approximately 8 healthy subjects will be participating in this study. A screening will be used to determine subject suitability for inclusion in the trial. Within one week after the screening visit, subjects who meet all inclusion criteria and none of the exclusion criteria will enter a one day treatment period. During this period, 4 anal manometric studies will take place. Study medication (Coated Phenylephrine suppositories at various doses) will be administered at pre-determined intervals. During the study, blood samples will be obtained for plasma Phenylephrine analysis.After determining baseline resting anal pressure with a manometric test, coated Suppositories will be administered intra rectally. Subjects will take rectally a total of 1 Coated Suppository per study. 60, 120 and 240 minutes after the coated suppository insertion amnometric studies will be performed: The first 2 subjects in the study will receive 40 mg phenyephrine coated suppositories. If significant (> 15%) increase in the resting anal pressure will occur with this dose, the rest of the study subjects will receive the same dose. If the raise in the resting anal pressure will not be significant AND no adverse events was observed, than the following subjects will receive 80 mg phenylehprine coated suppositories.