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CYP1A2 inhibition was the proposed mechanism; higher melatonin exposure does not imply better sleep while using caffeine.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Melatonin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"melatonin","display_name":"Melatonin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Twelve humans, six smokers and six nonsmokers","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"One substance can promote wakefulness while increasing blood exposure to another substance.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[melatonin-p14616429] Effects of caffeine intake on the pharmacokinetics of melatonin, a probe drug for CYP1A2 activity. (2003). https://pubmed.ncbi.nlm.nih.gov/14616429/ DOI: 10.1046/j.1365-2125.2003.01933.x","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Oral melatonin pharmacokinetics","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"43ccc5e4-17fa-5fdd-81ea-f4baf277f0ec","evidence_kind":"source_excerpt","locator":"Lines 708-719","start_line":708,"end_line":719,"excerpt":"### melatonin-caffeine-exposure\nConcurrent caffeine raised melatonin peak concentration by 142% and AUC by 120% on average.\nCondition category: normal\nnutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: One substance can promote wakefulness while increasing blood exposure to another substance.\norganism: Twelve humans, six smokers and six nonsmokers\ntissue_or_cell_type: Oral melatonin pharmacokinetics\nexperimental_model: Concurrent caffeine interaction study\nlimitations: Caffeine schedule and amount were study-specific. CYP1A2 inhibition was the proposed mechanism; higher melatonin exposure does not imply better sleep while using caffeine.\nexposure: 6 mg melatonin alone or with three 200 mg caffeine doses\nevidence_span: {\"source_cache\": \"artifacts/melatonin-research/14616429.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"6a8b06b9e1bcb570dca49735b73c2c7360a77381ae6fa25744bcccee7ceb52d8\", \"start_char\": 0, \"end_char\": 1070, \"text_sha256\": \"6a8b06b9e1bcb570dca49735b73c2c7360a77381ae6fa25744bcccee7ceb52d8\"}\n[melatonin-p14616429] Effects of caffeine intake on the pharmacokinetics of melatonin, a probe drug for CYP1A2 activity. 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