Comparing a 182mg Colon-targeted-delivery Peppermint Oil Capsule (Tempocol-ColoPulse®) and a 182mg Enteric-coated Peppermint Oil Capsule (Tempocol®), a Pharmacokinetic Study

This is a pilot study to compare the relative bioavailability between two peppermint oil formulations, namely a ileocolonic release peppermint oil and an small intestinal release peppermint oil (Tempocol®). This study is conducted as part of a future multicenter randomized controlled trial that will assess the therapeutic effect of the new peppermint oil formulation in IBS patients.

Rationale: Peppermint oil has shown to be effective in the treatment of IBS symptoms in several meta-analyses. However, the level of evidence is moderate and peppermint oil remains relatively under-used in IBS. Therefore the investigators plan to conduct a multicenter randomized controlled trial to investigate the possible beneficial effects of peppermint oil in IBS. To improve efficacy and to reduce side effects, the investigators aim to study the use of a new peppermint oil formulation that will slowly release the oil in the (ileo-) colonic region specifically. In order to demonstrate differences in pharmacokinetics, the subsidizing party, ZonMW, requested an additional pilot study (described in the present protocol) in which the investigators will investigate surrogate markers for local colon bioavailability, tolerability and side effects of the new ileocolonic release PO.

Study design: a randomized, double blind, two-period, two-treatment crossover study with a wash out period of at least 14 days.

Intervention: All study volunteers will receive a single dose of 182mg of both ileocolonic release peppermint oil and small intestinal release peppermint oil, each on a different test day.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Subjects may be confronted with certain inconveniences and minor risks. They are required to visit the MUMC+ 5 times, once for the screening and two times per test day for various non-invasive measurements (questionnaires, blood pressure and heart-rate measurement, urine and fecal sampling, pregnancy test in women in fertile ages, general physical exam) as well as for minor invasive venous blood sampling, after which a small haematoma can occur. Total time investment is +/- 30 hours, subjects will not benefit from participation.

Eligibility Criteria:
Inclusion Criteria:

* Based on medical history and previous examination, no gastrointestinal complaints can be defined
* Age between 18 and 65 years
* BMI between 18 and 25 kg/m2 and a weight of at least 50 kilograms
* Women in fertile age (\<55 years old) must use contraception or be postmenopausal for at least two years

Exclusion Criteria:

* History of severe or chronic cardiovascular, respiratory, urogenital, gastrointestinal/ hepatic, hematological/immunologic, HEENT (head, ears, eyes, nose, throat), dermatological/connective tissue, musculoskeletal, metabolic/nutritional, endocrine, neurological/psychiatric diseases, allergy, major surgery and/or laboratory assessments which might limit participation in or completion of the study protocol
* Use of medication, including vitamin and iron supplementation, except oral contraceptives, within 14 days prior to start of the study
* Administration of investigational drugs or participation in any scientific intervention study which may interfere with this study (to be decided by the principle investigator), in the 180 days prior to the study
* Major abdominal surgery interfering with gastrointestinal function (uncomplicated appendectomy, cholecystectomy and hysterectomy allowed, and other surgery upon judgment of the principle investigator)
* Dieting (for example lactose-free, gluten-free, caloric-restrictive, vegetarian or vegan, macrobiotic diet)
* Pregnancy, lactation
* High alcohol consumption (\>15 alcoholic consumptions per week)
* Smoking/ Using drugs of abuse
* Self-admitted HIV-positive state
* Known allergic reaction to peppermint
* High intake of caffeine (\>8 cups coffee a day)