* Have blood collected using three different methods before taking the two pills, 3 hours after taking the pills and 6 hours after taking the pills. The 3 methods include intravenous (IV) blood sampling, finger prick and collection on Whatman 903 Protein Saver Card and collection using the TASSO+ device. The TASSO+ blood collection device is a small capillary blood collection device that is designed to be easy to use and able to be used outside of a hospital/lab setting. Whatman 903 Protein Saver Cards are special filter paper with five circles for samples, that are designed for the collection and storage of blood. conditions: Healthy studyType: INTERVENTIONAL phases: EARLY_PHASE1 allocation: RANDOMIZED interventionModel: PARALLEL interventionModelDescription: An external party will prepare an equal number of kits (n=18) containing all the required materials for the participants, both in the placebo and caffeine group. They will assign a unique random number to each of the packages; each number will correlate to either the placebo or caffeine group. When a participant agrees to the study, they will be given a unique participant ID number ranging from 0-36. Then, the external party will use a random number generator to pick the kit given to that participant. They will record the number associated with that kit, and link the kit number to the participant ID for tracking purposes. At the end of the study, the investigators will determine which participants received caffeine vs placebo based on the assigned random numbers. primaryPurpose: OTHER masking: TRIPLE whoMasked: PARTICIPANT whoMasked: INVESTIGATOR whoMasked: OUTCOMES_ASSESSOR count: 36 type: ESTIMATED name: Caffeine Pill name: Placebo name: TASSO+ Device name: Finger prick and collection on Whatman Protein 903 Saver Cards name: Intravenous Sampling measure: Participant rate measure: Participant Adherence measure: Participant satisfaction measure: Significant changes in biomarkers observed after the ingestion of caffeine measure: Determine the correlation between capillary sampling and intravenous sampling measure: Determine the stability of capillary samples sex: ALL minimumAge: 18 Years maximumAge: 80 Years stdAges: ADULT stdAges: OLDER_ADULT facility: David Braley Research Institute city: Hamilton state: Ontario zip: L8L 2X2 country: Canada name: Luca Malatesta role: CONTACT phone: 905-527-4322 phoneExt: 40311 email: caffeine@crlb-gmel.ca name: Megan Robertson role: CONTACT phone: 905-527-527-4322 phoneExt: 40311 email: caffeine@crlb-gmel.ca name: Guillaume Pare, MD role: PRINCIPAL_INVESTIGATOR lat: 43.25011 lon: -79.84963 facility: Hamilton General Hospital city: Hamilton state: Ontario zip: L8L 2X2 country: Canada name: Luca Malatesta role: CONTACT phone: 905-527-4322 phoneExt: 40311 email: caffeine@crlb-gmel.ca name: Megan Robertson role: CONTACT phone: 905-527-4322 phoneExt: 40311 email: caffeine@crlb-gmel.ca name: Guillaume Pare, MD role: PRINCIPAL_INVESTIGATOR lat: 43.25011 lon: -79.84963 facility: McMaster University, Department of Pathology and Molecular Medicine city: Hamilton state: Ontario zip: L8S 4L8 country: Canada name: Luca Malatesta role: CONTACT phone: 905-527-4322 phoneExt: 40311 email: caffeine@crlb-gmel.ca name: Megan Robertson role: CONTACT phone: 905-527-4322 phoneExt: 40311 email: caffeine@crlb-gmel.ca name: Guillaume Pare, MD role: PRINCIPAL_INVESTIGATOR lat: 43.25011 lon: -79.84963 hasResults: False