2,4-Dinitrophenol
2,4-Dinitrophenol. A lipophilic protonophore that uncouples mitochondrial oxidative phosphorylation — shuttling protons across the inner membrane collapses the…
A lipophilic protonophore that uncouples mitochondrial oxidative phosphorylation — shuttling protons across the inner membrane collapses the electrochemical gradient, so substrate oxidation continues but ATP synthesis does not and the energy dissipates as heat. This drives a large rise in metabolic rate and fat oxidation (the basis of its illicit fat-loss use) but the same mechanism produces uncontrolled hyperthermia. DNP has no antidote and no therapeutic window — effective and lethal doses overlap, and its long persistence has caused many fatalities.
PubChem CID 1493. Protonophore, not a receptor ligand (no occupancy). The illicit weight-loss dose overlaps the lethal range. PK: an acute-overdose case (PMID:41249632) verbatim "demonstrating first order kinetics with a half-life of 18 h"; the commonly cited "~36 h" is not abstract-verifiable (see AUTHORING_GAPS). PK: STRIPPED. THE STORED HALF-LIFE IS BETTER SOURCED THAN I FEARED AND STILL CANNOT STAND. Its source is a SURVIVOR with serial ante-mortem levels — "Serial DNP levels are plotted for this patient, demonstrating first order kinetics with a half-life of 18 h" — not the post-mortem redistribution artefact I expected, and the existing note is accurate; credit where it is due. BUT IT IS A SINGLE PATIENT IN ACUTE-ON-CHRONIC OVERDOSE, no therapeutic human pharmacokinetics exist at all, and the historical literature is indexed without abstracts and measures metabolic rate rather than disposition. THE LARGEST LIVE HUMAN SERIES CONTRADICTS IT: its verbatim clearance percentages imply a half-life two and a half to three and a half times longer, AND THAT IS WITH HAEMOPERFUSION ACCELERATING ELIMINATION. And one sentence settles it structurally: "DNP exhibits significant NONLINEAR pharmacokinetics, which we have attributed to nonlinear plasma protein binding and nonlinear partitioning into liver and kidney" — which the solver cannot represent at any parameter choice. The dose block is unsourced and, as this record own note concedes, OVERLAPS THE LETHAL RANGE.
Sources: PMID:41249632