Persistent postsurgical abdominal pain (PPAP) is a very difficult to treat pain. This pain can persist for months or even years and significantly diminishes quality of life. The exact underlying cause for this pain persistence is still unclear, which makes its treatment still a challenge. The promising analgesic effects of Δ9-THC in previous research, plus the improved bioavailability of Namisol® in comparison with previous Δ9-THC substances form the basis of the present research proposal.

The current study aims to investigate the analgesic efficacy of Namisol® as add-on analgesic during a long-term treatment (52 days) of persistent postsurgical abdominal pain.

Inclusion Criteria:

• Aged 18 years or older
• Pain should have developed after a surgical procedure
• Pain duration exceeding 3 months, and average NRS≥3
• Stable doses intake of analgesics for the past 2 months
• The patient has been informed about the study, understood the information and signed the informed consent form

Exclusion Criteria:

• Diagnosed irritated bowel syndrome (IBS) or chronic pancreatitis
• Patient took cannabinoids on a regular basis for at least one year
• Patient does not feel a pinprick test in the lower extremities
• Patient has a body mass index (BMI) above 36,0 kg/m2
• Patient suffers from serious painful conditions other than chronic pancreatitis
• Patient has a significant medical disorder that may interfere with the study or may pose a risk for the patient
• Patient uses any kind of concomitant medication that may interfere with the study or may pose a risk for the patient
• Patient does not tolerate oral intake of medication or liquids, or is refrained from oral intake because of medical reasons
• Patient demonstrates clinical relevant deviations in the electrocardiogram (ECG)
• Patient has an actual moderate to severe renal impairment
• Patient has an actual moderate to severe hepatic impairment
• Patient has a presence or history of major psychiatric illness
• Patient has experienced an epileptic seizure in the past
• Patient demonstrates clinically significant laboratory abnormalities
• Patient demonstrates a positive urine drug screen for THC, cocaine, MDMA, and amphetamines
• Patient demonstrates a positive test result on hepatitis B surface antigen, hepatitis C antibody or HIV antibody test
• Patient has a history of sensitivity / idiosyncrasy to THC
• Patient has a known or suspected lactose intolerance
• Female patient is pregnant or breastfeeding
• Patient intends to conceive a child during the course of the study
• Patient participates in another investigational drug study
• Patient has a clinical significant exacerbation in illness
• Patient is unwilling or unable to comply with the lifestyle guidelines