L-Menthol Injection as a Novel Technique During Colonoscopy (MINT-C)

The primary objective of this double-blinded, prospective, randomized placebo-controlled study is to evaluate for change in endoscopic adenoma detection rates (ADR) with the use of peppermint oil solution vs placebo application during colonoscopy. The investigators hypothesize that ADR will be increased with the use of the peppermint oil solution and thus further reduce the risk of colon cancer by means of colonoscopy.

Adult subjects who are undergoing colonoscopy for primary colorectal cancer screening or surveillance. The study will be carried out as a prospective, double-blinded, fully-masked randomized controlled trial. Prior to the trial entry, the participant's labs and medical record will be reviewed in the electronic records system. If the subject meets inclusion/exclusion criteria, he or she will be consented at bedside prior undergoing their scheduled procedure and receive standard care as otherwise. Experimental and placebo solution ingredients will be serially numbered and randomized in a 1:1 ratio using a variable block strategy and provided by the institutional investigational pharmacy. Research staff will draw up experimental or placebo solution in 4 syringes with a total of 20mL in each solution. The solutions are identical in appearance and endoscopic delivery. To prevent olfactory detection of the peppermint oil solution an essential oil diffuser will be used in all endoscopy rooms using the same oil as in the experimental solution. Endoscopists will be instructed to deliver the contents of one syringe sprayed via the endoscope in the cecum and one in the sigmoid colon. The contents of the other two syringes are to be delivered at the discretion of the endoscopist. After the procedure, endoscopists and study participants will be surveyed to determine if blinding was effective and to assess patient comfort levels, respectively. The primary and secondary end points will be determined on an intention to treat basis.

Solution A) Peppermint oil solution (1.6% peppermint oil, which is 0.8% L-menthol) Ingredients: 16mL of peppermint oil (provided by the NowFoods® company) 0.4mL of Tween® 80 (i.e. Polysorbate 80) - this is a commonly used food additive that acts as a surfactant to bring the peppermint oil into solution 1L prepackage sterile water 2.6mL of undyed simethicone

Solution B) Placebo solution Ingredients: 0.4mL of Tween® 80 (i.e. Polysorbate 80) - this is a commonly used food additive that acts as a surfactant to bring the peppermint oil into solution 1L prepackage sterile water 2.6mL of undyed simethicone Instructions to prepare: Add tween and simethicone to sterile water. Then, shake vigorously. Once solution has settled, and patient has been randomized, draw 20mL of solution into a plastic syringe

During the colonoscopy the Endoscopists will be required to deliver intraluminally 1 syringe at the cecum and 1 syringe in the sigmoid colon. Up to 2 additional doses can be delivered at the discretion of the endoscopist up to a maximum of 4 total doses (max total dose = 640 mg of L-Menthol).

During the colonoscopy the Endoscopists will be required to deliver intraluminally 1 syringe at the cecum and 1 syringe in the sigmoid colon. Up to 2 additional doses can be delivered at the discretion of the endoscopist up to a maximum of 4 total doses (max total dose = 80 ml of Solution B, also has 0 mg of L-Menthol).

Evaluate for changes in adenoma detection rates with the use of intraluminal peppermint oil application vs sterile water application during colonoscopy.

Evaluate for changes in total procedure time, cecal intubation time, and withdrawal time with the use of intraluminal peppermint oil application vs sterile water application during colonoscopy.

Evaluate for changes in advanced adenoma detection rates with the use of intraluminal peppermint oil application vs placebo during coloscopy. Advanced adenoma will be define as an adenoma with significant villous features (>25%), size of 1.0 cm or more, high-grade dysplasia, or early invasive cancer.

Evaluate for changes in cancer detection rates with the use of intraluminal peppermint oil application vs placebo during colonoscopy.

Evaluate for changes in reported patient comfort levels with the use of intraluminal peppermint oil application vs placebo during colonoscopy.

Inclusion Criteria: At least 50 years of age in Caucasians or 45 years of age in African-Americans. Patients undergoing primary screening colonoscopy (either average risk or increased-risk) or surveillance colonoscopy after prior screening/surveillance colonoscopy. Capable of understanding instructions, adhering to study schedules and requirements, and willing to provide informed consent. Exclusion Criteria: History of colectomy, partial or complete Symptoms suggesting possible colorectal stenosis or cancer Inflammatory bowel disease Familial polyposis syndromes History of, or current diagnosis of colorectal cancer American Society of Anesthesia Physical Stats (ASA PS) score of IV or greater Non-correctable coagulopathy Currently receiving anti-thrombotic therapy, with an INR > 1.5 Poor prep, total BBPS score < 6, or any part of the colon < 2. Patients with known allergy to peppermint oil or peppermint containing products. Patients taking calcium channel blockers (Amlodipine, Nifedipine, Verapamil, Diltiazem, Dihydropyridine, Felodipine, etc).