The objective of the investigation is to evaluate the feasibility of detecting blood in healthy volunteers after ingestion of autologous blood mixed with water.

A total of 10 healthy volunteers were recruited to undergo a testing procedure. Subjects were instructed to ingest the PillSense Capsule with 100mL of water. The position of the capsule in the stomach was verified by fluoroscopy. Subjects were then asked to sequentially drink (every 5min) 2 mixtures containing 25mL of water and 25mL of their own blood obtained from a peripheral vein. The PillSense result ("blood detected" or " blood not detected") was recorded on Clinical Report Form after 5 minutes from capsule ingestion and after 5 minutes from the ingestion of both mixtures containing blood.

Subjects were followed-up for capsule passing.

Inclusion Criteria:

1. Age 18 -60 years
2. Ability to give written informed consent

Exclusion Criteria:

1. Circulatory or hemodynamic instability with a clear need for urgent endoscopy or surgery (systolic blood pressure <100 mmHg,heart rate > 100 / min)
2. Known current stenosis of the GI tract
3. Presence of pacemaker or other implantable electronic device
4. Dysphagia or difficulties in swallowing pills the size of the capsule
5. History of achalasia or known esophageal dysmotility
6. History of gastroparesis
7. History of severe constipation (1 bowel movement per week or less)
8. Healthy volunteers who are currently pregnant or breastfeeding, or intend to become pregnant during the investigation
9. Active psychological issues preventing participation
10. Stomach bezoar
11. History of severe esophagitis
12. History of Crohn disease
13. History of diverticulitis
14. History of bowel obstruction
15. Suspected gastrointestinal tumor disease
16. Planned MRI investigation (MRI needed before the capsule is excreted)