Location: Children's Nutrition Research CenterTitle: Systemic exposure to menthol following administration of peppermint oil to paediatric patients Author
Submitted to: BMJ Open
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/15/2015
Publication Date: 7/14/2015
Citation: Kearns, G.L., Chumpitazi, B.P., Abdel-Rahman, S.M., Garg, U., Shulman, R.J. 2015. Systemic exposure to menthol following administration of peppermint oil to paediatric patients. BMJ Open. 5(8):e008375. Interpretive Summary: Peppermint oil (PMO) has been used to treat abdominal problems dating to ancient Egypt, Greece and Rome. Despite the fact it is used in children, little is known about how the body metabolizes (breaks down) PMO. We studied in a small group of children how the body handles PMO. We found that the form of PMO given to a child is very important in how the body metabolizes the medication. We can now carry out studies which examine what effects PMO has on the gastrointestinal tract.
Technical Abstract: Peppermint oil (PMO) has been used to treat abdominal ailments dating to ancient Egypt, Greece and Rome. Despite its increasing paediatric use, as in irritable bowel syndrome (IBS) treatment, the pharmacokinetics (PK) of menthol in children given PMO has not been explored. Single-site, exploratory pilot study of menthol PK following a single 187 mg dose of PMO. Subjects with paediatric Rome II defined (IBS; n=6, male and female, 7-15 years of age) were enrolled. Blood samples were obtained before PMO administration and at 10 discrete time points over a 12 h postdose period. Menthol was quantitated from plasma using a validated gas chromatography mass spectrometry technique. Menthol PK parameters were determined using a standard non-compartmental approach. Following a dose of PMO, a substantial lag time (range 1-4 h) was seen in all subjects for the appearance of menthol which in turn, produced a delayed time of peak (Tmax=5.3 +/- 2.4 h) plasma concentration (Cmax=698.2 +/- 245.4 ng/mL). Tmax and Tlag were significantly more variable than the two exposure parameters; Cmax, mean residence time and total area under the curve (AUC=4039.7 +/- 583.8 ng/mL × h) which had a coefficient of variation of <20%. Delayed appearance of menthol in plasma after oral PMO administration in children is likely a formulation-specific event which, in IBS, could increase intestinal residence time of the active ingredient. Our data also demonstrate the feasibility of using menthol PK in children with IBS to support definitive studies of PMO dose-effect relationships.