--- title: "Paraxanthine: Research & Evidence | BodyHackGuide" url: https://www.bodyhackguide.co/compound/paraxanthine description: "Paraxanthine: mechanism, clinical studies & side effects." lang: en --- Skip to content Compare notes on r/BodyHackGuide (https://reddit.com/r/bodyhackguide) Compare notes with other researchers. Join r/BodyHackGuide (https://reddit.com/r/bodyhackguide) Image: Paraxanthine molecular structure (https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/4687/PNG?image_size=300x300) # Paraxanthine Nootropics (https://www.bodyhackguide.co/wiki#cat-nootropics)Supplement Also known as: 1,7-Dimethylxanthine, p-Xanthine, 1,7-Dimethyl-3H-purine-2,6-dione, PXN Paraxanthine (1,7-dimethylxanthine) is the main breakdown product of caffeine in humans, formed when the liver enzyme CYP1A2 removes one methyl group from caffeine, and it is also made synthetically and sold as a stimulant ingredient in dietary supplements (PMID: 8529334, PMID: 1302044, PMID: 34597720). In a 1986 study that gave each compound to the same six men, paraxanthine had a half-life of 3.1 hours against 4.1 hours for caffeine, with a similar clearance (PMID: 3756065). Price check No vendor listings yet We do not track a vendor for Paraxanthine yet. Compare other compounds: https://www.bodyhackguide.co/compare Half-life: About 3.1 hours in a 1986 study that gave paraxanthine by mou… Route: Oral MW: 180.16 g/mol CAS: 611-59-6 Last reviewed: Oct 21, 2026 ## Overview ### At A Glance Mechanism How the body makes paraxanthine from caffeine… Half-Life About 3.1 hours in a 1986 study that gave paraxanthine by mouth to 6 healthy men, against 4.1 hours for caffeine in the same men (PMID: 3756065). Routes Oral Potential Benefits Card-sorting errors and short-term memory reaction times in a 13-person crossover trial (PMID: 34836235) Cognitive test scores after a 10-km run in 12 trained runners (PMID: 38725238) Resting energy expenditure at 200 mg in a 21-person crossover trial (PMID: 38745415) Subjective sleep quality compared with caffeine in a 14-rower crossover trial (PMID: 41918248) Free fatty acid release similar to caffeine at 4 mg/kg in a 12-person crossover study (PMID: 8529334) Wakefulness in normal and narcoleptic mice (PMID: 20614853) ### Mechanism of Action ### How the body makes paraxanthine from caffeine In tests of individual human liver enzymes, CYP1A2 alone removed the methyl group at position 3 of caffeine (3-demethylation), the step that yields paraxanthine, and the products of CYP1A2's caffeine metabolism were 81.5 percent paraxanthine, 10.8 percent theobromine and 5.4 percent theophylline (PMID: 1302044). In people, caffeine is converted on average 80 percent to paraxanthine, and with regular caffeine intake serum paraxanthine averages two thirds of the caffeine level (PMID: 8529334). Because CYP1A2 makes it, the ratio of paraxanthine to caffeine in plasma or saliva is used as a test of a person's CYP1A2 activity (PMID: 7920690). This fits BodyHackGuide's caffeine (https://www.bodyhackguide.co/compound/caffeine) guide, which names CYP1A2 as the main enzyme of caffeine metabolism. ### Adenosine receptors Caffeine and paraxanthine both block adenosine receptors competitively and without selectivity for receptor subtype in laboratory tests (PMID: 8529334). In a 12-person crossover study, oral paraxanthine and oral caffeine at 4 mg/kg raised diastolic blood pressure, plasma epinephrine and free fatty acids to a similar degree, while at 2 mg/kg caffeine appeared to produce larger responses (PMID: 8529334). After intravenous caffeine in 10 men, the rise in blood free fatty acids tracked the appearance of paraxanthine (r=0.93) (PMID: 2312486). ### A second mechanism in rats: cGMP, nitric oxide and dopamine At the National Institute on Drug Abuse, paraxanthine produced stronger locomotor activation in rats than caffeine, theophylline or theobromine (PMID: 23261866). Its effects were reduced by blocking nitric oxide synthesis, and paraxanthine but not caffeine raised cyclic GMP (cGMP) and extracellular dopamine in the rat striatum, which the authors attributed to inhibition of a cGMP-preferring phosphodiesterase (PDE9) (PMID: 23261866). In normal and narcoleptic mice dosed during the light period, paraxanthine promoted wakefulness more strongly and for longer than an equimolar dose of caffeine, and it produced less anxiety-like behavior (PMID: 20614853). ### Pharmacokinetics compared with caffeine In six healthy men given each compound by mouth on separate occasions, total plasma clearance was 2.07 mL/min/kg for caffeine and 2.20 mL/min/kg for paraxanthine, half-lives were 4.1 and 3.1 hours, and volumes of distribution were similar (PMID: 3756065). Paraxanthine itself is cleared mainly by further demethylation: products of 7-demethylation accounted for 67 percent of its clearance and unchanged paraxanthine in urine for 9 percent, and the cytochrome P450 inhibitor cimetidine cut its plasma clearance by 30 percent (PMID: 2913277). CYP1A2 alone carried out paraxanthine 7-demethylation in tests of individual human enzymes (PMID: 1302044). ### Overview Paraxanthine (1,7-dimethylxanthine) is the main breakdown product of caffeine in humans, formed when the liver enzyme CYP1A2 removes one methyl group from caffeine, and it is also made synthetically and sold as a stimulant ingredient in dietary supplements (PMID: 8529334, PMID: 1302044, PMID: 34597720). In a 1986 study that gave each compound to the same six men, paraxanthine had a half-life of 3.1 hours against 4.1 hours for caffeine, with a similar clearance (PMID: 3756065). The recent human trials of paraxanthine as a supplement are small crossover studies of 12 to 21 participants, and four of the five found list coauthors affiliated with the company that supplies the ingredient (PMID: 34836235, PMID: 38745415, PMID: 41918248). Rat toxicology studies of two suppliers' paraxanthine found no genotoxicity and no adverse effects over 90 days at the doses tested (PMID: 34597720, PMID: 36818692), and a search of the FDA's GRAS Notice Inventory on 20 October 2026 found no GRAS notice for paraxanthine. ### Potential Research Fields Caffeine metabolism CYP1A2 pharmacology Adenosine receptor pharmacology Cognitive performance Sports nutrition Toxicology ## Chemical Information IUPAC Name Not yet available CAS Number 611-59-6 Molecular Formula C7H8N4O2 Molecular Mass 180.16 g/mol View on PubChem: https://pubchem.ncbi.nlm.nih.gov/compound/4687 ## Dosing & Protocols ### Unlock the Dosing tab Enter your email to keep reading. It is free, and it opens these tabs on every compound page in this browser. - Route You also get the free peptide cheat sheet by email. Unsubscribe anytime. Have an account? Sign in (https://www.bodyhackguide.co/auth) ## Research ### Unlock the research summary - A summary of the key research - Safety and side effects - A link to the PubMed results ## Interactions ### Interaction Matrix ### Contraindications **Caffeine sensitivity and cardiovascular conditions.** Paraxanthine had sympathomimetic effects similar to caffeine at 4 mg/kg in a human study, raising diastolic blood pressure and plasma epinephrine (PMID: 8529334), so the cautions covered on BodyHackGuide's caffeine (https://www.bodyhackguide.co/compound/caffeine) page apply by mechanism. **Combining with caffeine.** Paraxanthine is the main product of caffeine metabolism (PMID: 8529334), so caffeine intake adds to paraxanthine exposure. **Drugs that slow its clearance.** Cimetidine reduced paraxanthine clearance by 30 percent in humans (PMID: 2913277), and CYP1A2 carries out its main clearance step (PMID: 1302044), so CYP1A2 inhibitors are a mechanism-based reason for caution. **Pregnancy.** No human data on paraxanthine supplements were found; high injected doses caused malformations in mice (PMID: 3798364), and very high maternal serum paraxanthine was linked to spontaneous abortion in a caffeine-exposure study (PMID: 10572151). Research Disclaimer This interaction data is compiled from published research and community reports. It may not be exhaustive. Always consult a healthcare professional before combining compounds. No listings found for Paraxanthine. ### Sign in to leave a review Reviews on BodyHackGuide are tied to verified user accounts and moderated before publishing. Sign in (free, no spam) to share your experience with Paraxanthine. ### Related Compounds View All (https://www.bodyhackguide.co/wiki) ### 9-Me-BC (9-Methyl-β-carboline) Nootropics Preclinical 9-Methyl--carboline (9-Me-BC) is a synthetic -carboline alkaloid that has drawn nootropic-community interest for a preclinical property that is genuinely unusual among -carbolines: in rodent and cell-culture studies it appears to stimulate the dopaminergic phenotype - raising tyrosine hydroxylase, the number of differentiated dopamine neurons and dopamine content - while also showing neuroprotective, neurorestorative and anti-inflammatory effects, plus in-vitro MAO-A/MAO-B inhibition [PMID:17913302, PMID:20374418, PMID:32285253]. t½ Not characterized in humans (no pharmacokinetic data). Community/anecdotal only: ~5-25 mg per day, oral. No validated or approved human dose exists. 6 PubMed View Profile https://www.bodyhackguide.co/compound/9-mbc ### Aniracetam Nootropics Approved (Italy) Aniracetam is a pyrrolidinone in the racetam family, developed by Hoffmann-La Roche under the code Ro 13-5057. t½ About half an hour for the parent drug in humans. Plasma elimination half-life was 0.47 to 0.49 hours after a single 400 mg oral dose in 20 healthy male volunteers (PMID: 19025058). Aniracetam is extensively metabolized to N-anisoyl-GABA and anisic acid; in six elderly hospitalized patients with cerebrovascular disease and reduced creatinine clearance, metabolite half-life was 4 to 7 times longer than in young volunteers (PMID: 9062694). Preclinical View Profile https://www.bodyhackguide.co/compound/aniracetam ### Bemethyl (bemitil) Nootropics Approved (Russia) Bemethyl, known in the Russian literature as bemitil and sold in the region under names including Metaprot, Bemactor and Antihot, is 2-ethylthiobenzimidazole, normally handled as the hydrobromide salt. t½ Not established in humans; in healthy volunteers given a single 250 mg oral dose of the Metaprot capsule form, peak serum ethylthiobenzimidazole averaged 0.91 microg/mL at about 1.06 h, and no terminal half-life was reported (PMID: 21870773) Preclinical View Profile https://www.bodyhackguide.co/compound/bemethyl ### Bromantane Nootropics Russia Approved Bromantane is an atypical psychostimulant and anxiolytic developed in the 1980s at the Zakusov Institute of Pharmacology of the Russian Academy of Medical Sciences, originally created as an adaptogen for Soviet military and elite athletic use and later approved in Russia for the treatment of neurasthenic and asthenic disorders under the trade name Ladasten. 34 PubMed View Profile https://www.bodyhackguide.co/compound/bromantane ### Cyclazodone Nootropics Preclinical Cyclazodone is the N-cyclopropyl derivative of pemoline, a 4-oxazolidinone stimulant. Preclinical View Profile https://www.bodyhackguide.co/compound/cyclazodone ### Dihexa Nootropics Preclinical Dihexa is a synthetic peptide analogue of the angiotensin IV metabolite LVV-hemorphin-7, developed at Washington State University. t½ Not characterized in humans. Dihexa was engineered for metabolic stability (resistant to plasma and enzymatic degradation) and blood-brain-barrier penetration; in preclinical work its central procognitive effects appear to outlast its plasma presence. 5 to 40 mg oral per day (anecdotal range; no established human dose) 1 PubMed View Profile https://www.bodyhackguide.co/compound/dihexa View Full Dosage Guide → Protocols, calculator & safety for Paraxanthine https://www.bodyhackguide.co/guides/dosage/paraxanthine ### Price check No vendor listings yet See the vendor scorecard (https://www.bodyhackguide.co/vendors/scorecard) ### Research Score 30 0 PubMed results ### Quality Indicators Data Completeness 63% Description Mechanism of Action Chemical Data Dosing Protocols Safety Profile PubMed Results Interactions Vendor Listings ### Quick Facts Half-Life Molecular Weight 180.16 g/mol Administration Oral CAS Number 611-59-6 Trial Phase Supplement Research Disclaimer This information is for educational and research purposes only. Not intended as medical advice. Consult a healthcare professional before use. ## Frequently Asked Questions What is paraxanthine? Paraxanthine (1,7-dimethylxanthine) is the main metabolite of caffeine in humans, and on average about 80 percent of caffeine is converted to paraxanthine (PMID: 8529334). Paraxanthine is formed from caffeine by the liver enzyme CYP1A2 (PMID: 1302044). Paraxanthine is also made synthetically and sold as a dietary supplement ingredient (PMID: 34597720). How is paraxanthine different from caffeine? Paraxanthine and caffeine both block adenosine receptors, and at 4 mg/kg paraxanthine raised blood pressure, epinephrine and free fatty acids about as much as caffeine in 12 people (PMID: 8529334). In six men given each compound, paraxanthine had a half-life of 3.1 hours against 4.1 hours for caffeine (PMID: 3756065). In rats, paraxanthine but not caffeine raised striatal cGMP and dopamine, which points to an additional mechanism (PMID: 23261866). Does paraxanthine improve focus or memory? In a 13-person crossover trial, a single 200 mg dose of paraxanthine reduced card-sorting errors and sped some memory reaction times compared with placebo (PMID: 34836235). In a 12-person paraxanthine dose comparison, the main between-treatment test showed only a trend, with other differences found by comparing changes from baseline (PMID: 34960030). Most paraxanthine trials had coauthors affiliated with the ingredient's supplier (PMID: 34836235, PMID: 38725238). Does paraxanthine affect sleep less than caffeine? In a 14-rower crossover study, conditions containing caffeine were linked to poorer subjective sleep, while paraxanthine alone showed more favorable sleep outcomes (PMID: 41918248). The 14-rower paraxanthine study measured sleep only by questionnaire (PMID: 41918248). In mice, paraxanthine promoted wakefulness more strongly and for longer than an equal molar dose of caffeine (PMID: 20614853). Does paraxanthine improve exercise performance? In 14 rowers, paraxanthine alone did not clearly improve 2,000-m ergometer performance, while paraxanthine combined with caffeine did (PMID: 41918248). In 12 trained runners, paraxanthine improved some cognitive test scores after a 10-km run, and the outcomes reported for that paraxanthine study were cognitive tests rather than running times (PMID: 38725238). Mouse data showing more muscle and endurance with paraxanthine came from authors affiliated with the ingredient's supplier (PMID: 35215543). Is paraxanthine safe? Paraxanthine trials of a single dose to 7 days of daily use found no differences from placebo in blood chemistry or reported side effects (PMID: 34960030, PMID: 38725238). At 4 mg/kg, paraxanthine raised diastolic blood pressure and plasma epinephrine about as much as caffeine in 12 people (PMID: 8529334). Rat studies of two suppliers' paraxanthine found no genotoxicity and no adverse effects over 90 days at up to 185 to 300 mg/kg a day (PMID: 34597720, PMID: 36818692). No long-term human safety data on paraxanthine were found, and high injected doses of paraxanthine caused malformations in pregnant mice (PMID: 3798364). What is paraxanthine's regulatory status in the US? Paraxanthine is sold in the United States as an ingredient in products labeled as dietary supplements (NIH Dietary Supplement Label Database). Searches on 20 October 2026 found no paraxanthine drug in Drugs@FDA, no GRAS notice for paraxanthine in the FDA's GRAS Notice Inventory, and no new dietary ingredient notification for paraxanthine on regulations.gov. ## Research Tools ### Peptide Calculator Reconstitution & syringe units https://www.bodyhackguide.co/tools/reconstitution ### Reconstitution Guide How to mix, step by step https://www.bodyhackguide.co/guides/how-to-reconstitute-peptides ### Nasal Spray Calc mL per actuation https://www.bodyhackguide.co/tools/intranasal ### Half-Life Visualizer Decay curves https://www.bodyhackguide.co/tools/halflife ## You may also like ### Cyclazodone Nootropics View product (https://www.bodyhackguide.co/buy/cyclazodone) ### Fladrafinil (CRL-40,941) Nootropics View product (https://www.bodyhackguide.co/buy/fladrafinil) ### Bromantane Nootropics View product (https://www.bodyhackguide.co/buy/bromantane) ### Bemethyl (bemitil) Nootropics View product (https://www.bodyhackguide.co/buy/bemethyl) ## Related Compounds ### 9-Me-BC (9-Methyl-β-carboline) Nootropics Preclinical ### Aniracetam Nootropics Approved (Italy) ### Bemethyl (bemitil) Nootropics Approved (Russia) ### Bromantane Nootropics Russia Approved ### Cyclazodone Nootropics Preclinical ### Dihexa Nootropics Preclinical Free 2026 Peptide Cheat Sheet (PDF) 38 compounds and blends: vial sizes, BAC water volumes, dosing ranges and bloodwork markers. 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All rights reserved. · Terms (https://www.bodyhackguide.co/terms) · Privacy (https://www.bodyhackguide.co/privacy) ## Structured data ```json [ { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://www.bodyhackguide.co/" }, { "@type": "ListItem", "position": 2, "name": "Compounds", "item": "https://www.bodyhackguide.co/compare" }, { "@type": "ListItem", "position": 3, "name": "Paraxanthine" } ] }, { "@context": "https://schema.org", "@type": "MedicalWebPage", "name": "Paraxanthine", "description": "Paraxanthine (1,7-dimethylxanthine) is the main breakdown product of caffeine in humans, formed when the liver enzyme CYP1A2 removes one methyl group from caffeine, and it is also made synthetically and sold as a stimulant ingredient in dietary supplements (PMID: 8529334, PMID: 1302044, PMID: 34597720). In a 1986 study that gave each compound to the same six men, paraxanthine had a half-life of 3.1 hours against 4.1 hours for caffeine, with a similar clearance (PMID: 3756065). The recent human trials of paraxanthine as a supplement are small crossover studies of 12 to 21 participants, and four of the five found list coauthors affiliated with the company that supplies the ingredient (PMID: 34836235, PMID: 38745415, PMID: 41918248). Rat toxicology studies of two suppliers' paraxanthine found no genotoxicity and no adverse effects over 90 days at the doses tested (PMID: 34597720, PMID: 36818692), and a search of the FDA's GRAS Notice Inventory on 20 October 2026 found no GRAS notice for paraxanthine.", "lastReviewed": "2026-10-21T06:27:34.891Z", "url": "https://www.bodyhackguide.co/compound/paraxanthine", "author": { "@type": "Person", "name": "BioChonch", "url": "https://www.bodyhackguide.co/about", "jobTitle": "Founder & Lead Researcher", "sameAs": [ "https://reddit.com/r/BodyHackGuide", "https://reddit.com/r/BrainHackGuide", "https://reddit.com/r/Biohackingher" ], "worksFor": { "@type": "Organization", "name": "BodyHackGuide", "url": "https://www.bodyhackguide.co" } }, "reviewedBy": { "@type": "Person", "name": "BioChonch", "url": "https://www.bodyhackguide.co/about", "jobTitle": "Founder & Lead Researcher", "sameAs": [ "https://reddit.com/r/BodyHackGuide", "https://reddit.com/r/BrainHackGuide", "https://reddit.com/r/Biohackingher" ], "worksFor": { "@type": "Organization", "name": "BodyHackGuide", "url": "https://www.bodyhackguide.co" } }, "publisher": { "@type": "Organization", "name": "BodyHackGuide", "url": "https://www.bodyhackguide.co" }, "mainContentOfPage": { "@type": "WebPageElement", "cssSelector": "main" }, "about": { "@type": "Drug", "name": "Paraxanthine", "alternateName": [ "1,7-Dimethylxanthine", "p-Xanthine", "1,7-Dimethyl-3H-purine-2,6-dione", "PXN" ], "description": "Paraxanthine (1,7-dimethylxanthine) is the main breakdown product of caffeine in humans, formed when the liver enzyme CYP1A2 removes one methyl group from caffeine, and it is also made synthetically and sold as a stimulant ingredient in dietary supplements (PMID: 8529334, PMID: 1302044, PMID: 34597720). In a 1986 study that gave each compound to the same six men, paraxanthine had a half-life of 3.1 hours against 4.1 hours for caffeine, with a similar clearance (PMID: 3756065). The recent human trials of paraxanthine as a supplement are small crossover studies of 12 to 21 participants, and four of the five found list coauthors affiliated with the company that supplies the ingredient (PMID: 34836235, PMID: 38745415, PMID: 41918248). Rat toxicology studies of two suppliers' paraxanthine found no genotoxicity and no adverse effects over 90 days at the doses tested (PMID: 34597720, PMID: 36818692), and a search of the FDA's GRAS Notice Inventory on 20 October 2026 found no GRAS notice for paraxanthine.", "activeIngredient": "Paraxanthine", "administrationRoute": "Oral", "mechanismOfAction": "How the body makes paraxanthine from caffeine In tests of individual human liver enzymes, CYP1A2 alone removed the methyl group at position 3 of caffeine (3-demethylation), the step that yields paraxanthine, and the products of CYP1A2's caffeine metabolism were 81.5 percent paraxanthine, 10.8 percent theobromine and 5.4 percent theophylline (PMID: 1302044). In people, caffeine is converted on average 80 percent to paraxanthine, and with regular caffeine intake serum paraxanthine averages two thirds of the caffeine level (PMID: 8529334). Because CYP1A2 makes it, the ratio of paraxanthine to caffeine in plasma or saliva is used as a test of a person's CYP1A2 activity (PMID: 7920690). This fits BodyHackGuide's caffeine guide, which names CYP1A2 as the main enzyme of caffeine metabolism. Adenosine receptors Caffeine and paraxanthine both block adenosine receptors competitively and without selectivity for receptor subtype in laboratory tests (PMID: 8529334). In a 12-person crossover study, oral paraxanthine and oral caffeine at 4 mg/kg raised diastolic blood pressure, plasma epinephrine and free fatty acids to a similar degree, while at 2 mg/kg caffeine appeared to produce larger responses (PMID: 8529334). After intravenous caffeine in 10 men, the rise in blood free fatty acids tracked the appearance of paraxanthine (r=0.93) (PMID: 2312486). A second mechanism in rats: cGMP, nitric oxide and dopamine At the National Institute on Drug Abuse, paraxanthine produced stronger locomotor activation in rats than caffeine, theophylline or theobromine (PMID: 23261866). Its effects were reduced by blocking nitric oxide synthesis, and paraxanthine but not caffeine raised cyclic GMP (cGMP) and extracellular dopamine in the rat striatum, which the authors attributed to inhibition of a cGMP-preferring phosphodiesterase (PDE9) (PMID: 23261866). In normal and narcoleptic mice dosed during the light period, paraxanthine promoted wakefulness more strongly and for longer than an equimolar dose of caffeine, and it produced less anxiety-like behavior (PMID: 20614853). Pharmacokinetics compared with caffeine In six healthy men given each compound by mouth on separate occasions, total plasma clearance was 2.07 mL/min/kg for caffeine and 2.20 mL/min/kg for paraxanthine, half-lives were 4.1 and 3.1 hours, and volumes of distribution were similar (PMID: 3756065). Paraxanthine itself is cleared mainly by further demethylation: products of 7-demethylation accounted for 67 percent of its clearance and unchanged paraxanthine in urine for 9 percent, and the cytochrome P450 inhibitor cimetidine cut its plasma clearance by 30 percent (PMID: 2913277). CYP1A2 alone carried out paraxanthine 7-demethylation in tests of individual human enzymes (PMID: 1302044).", "legalStatus": "Not approved for human use (research chemical)", "warning": "For research purposes only. Not for human consumption." } }, { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "What is paraxanthine?", "acceptedAnswer": { "@type": "Answer", "text": "Paraxanthine (1,7-dimethylxanthine) is the main metabolite of caffeine in humans, and on average about 80 percent of caffeine is converted to paraxanthine (PMID: 8529334). Paraxanthine is formed from caffeine by the liver enzyme CYP1A2 (PMID: 1302044). Paraxanthine is also made synthetically and sold as a dietary supplement ingredient (PMID: 34597720)." } }, { "@type": "Question", "name": "How is paraxanthine different from caffeine?", "acceptedAnswer": { "@type": "Answer", "text": "Paraxanthine and caffeine both block adenosine receptors, and at 4 mg/kg paraxanthine raised blood pressure, epinephrine and free fatty acids about as much as caffeine in 12 people (PMID: 8529334). In six men given each compound, paraxanthine had a half-life of 3.1 hours against 4.1 hours for caffeine (PMID: 3756065). In rats, paraxanthine but not caffeine raised striatal cGMP and dopamine, which points to an additional mechanism (PMID: 23261866)." } }, { "@type": "Question", "name": "Does paraxanthine improve focus or memory?", "acceptedAnswer": { "@type": "Answer", "text": "In a 13-person crossover trial, a single 200 mg dose of paraxanthine reduced card-sorting errors and sped some memory reaction times compared with placebo (PMID: 34836235). In a 12-person paraxanthine dose comparison, the main between-treatment test showed only a trend, with other differences found by comparing changes from baseline (PMID: 34960030). Most paraxanthine trials had coauthors affiliated with the ingredient's supplier (PMID: 34836235, PMID: 38725238)." } }, { "@type": "Question", "name": "Does paraxanthine affect sleep less than caffeine?", "acceptedAnswer": { "@type": "Answer", "text": "In a 14-rower crossover study, conditions containing caffeine were linked to poorer subjective sleep, while paraxanthine alone showed more favorable sleep outcomes (PMID: 41918248). The 14-rower paraxanthine study measured sleep only by questionnaire (PMID: 41918248). In mice, paraxanthine promoted wakefulness more strongly and for longer than an equal molar dose of caffeine (PMID: 20614853)." } }, { "@type": "Question", "name": "Does paraxanthine improve exercise performance?", "acceptedAnswer": { "@type": "Answer", "text": "In 14 rowers, paraxanthine alone did not clearly improve 2,000-m ergometer performance, while paraxanthine combined with caffeine did (PMID: 41918248). In 12 trained runners, paraxanthine improved some cognitive test scores after a 10-km run, and the outcomes reported for that paraxanthine study were cognitive tests rather than running times (PMID: 38725238). Mouse data showing more muscle and endurance with paraxanthine came from authors affiliated with the ingredient's supplier (PMID: 35215543)." } }, { "@type": "Question", "name": "Is paraxanthine safe?", "acceptedAnswer": { "@type": "Answer", "text": "Paraxanthine trials of a single dose to 7 days of daily use found no differences from placebo in blood chemistry or reported side effects (PMID: 34960030, PMID: 38725238). At 4 mg/kg, paraxanthine raised diastolic blood pressure and plasma epinephrine about as much as caffeine in 12 people (PMID: 8529334). Rat studies of two suppliers' paraxanthine found no genotoxicity and no adverse effects over 90 days at up to 185 to 300 mg/kg a day (PMID: 34597720, PMID: 36818692). No long-term human safety data on paraxanthine were found, and high injected doses of paraxanthine caused malformations in pregnant mice (PMID: 3798364)." } }, { "@type": "Question", "name": "What is paraxanthine's regulatory status in the US?", "acceptedAnswer": { "@type": "Answer", "text": "Paraxanthine is sold in the United States as an ingredient in products labeled as dietary supplements (NIH Dietary Supplement Label Database). Searches on 20 October 2026 found no paraxanthine drug in Drugs@FDA, no GRAS notice for paraxanthine in the FDA's GRAS Notice Inventory, and no new dietary ingredient notification for paraxanthine on regulations.gov." } } ] }, { "@context": "https://schema.org", "@type": "Organization", "@id": "https://www.bodyhackguide.co#organization", "name": "BodyHackGuide", "alternateName": "BHG", "url": "https://www.bodyhackguide.co", "logo": { "@type": "ImageObject", "url": "https://www.bodyhackguide.co/logo.png", "width": 512, "height": 512 }, "description": "Evidence-based research reference for peptides and nootropics. 273 compound profiles, interactive dosing calculators, vendor price comparisons, and trust-scored vendor reviews scored on a public, reproducible methodology applied to every vendor. 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