Skip to main content

Severe toxicity after use of 2,4-dinitrophenol reported to the UK National Poisons Information Service

Author/s Kamour A, Gwynnette D, George N, Cooper G, Lupton DJ, Eddleston M, Thompson JP, Vale JA, Thanacoody RHK, Hill S, Thomas SHL
Year 2014
Type of publication Conference proceeding

Background: 2,4-Dinitrophenol (DNP) was introduced as a weight-losing drug in the United States during the 1930s but was banned as a result of serious adverse effects and fatalities. DNP use has increased in popularity worldwide recently as an aid to weight loss, but severe toxicity and fatalities have been reported.

Objective: This study was performed to characterize the toxicity of DNP reported to the UK National Poisons Information Service (NPIS).

Methods: NPIS telephone enquiry records and user sessions for TOXBASE®, the NPIS online information database, involving systemic exposures to DNP were reviewed for the period January 1, 2007 to August 15, 2013.

Results: Of 23 exposures (20 males, 3 females; median age, 24 years) reported by telephone, there were 3 during 2007–2011, 5 during 2012, and 15 during 2013 (to August 15th). TOXBASE® user sessions also increased sharply from 6 in 2011 to 35 in 2012 and 127 in 2013. Exposure was reported as chronic (n = 15), acute (n = 6), acute on chronic (n = 1), and unknown (n = 1). Commonly reported features were fever (61%), tachycardia (57%), sweating (39%), skin discoloration or rash (35%), nausea or vomiting (22%), abdominal pain (17%), and headache (17%). Agitation, metabolic acidosis, and chest pain were each reported in 13% of cases. There were five (22%; 95% confidence intervals 8%, 44%) fatalities, three involving acute exposure.

Conclusion: There has been a recent increase in DNP exposures reported to the NPIS by telephone and in accesses to TOXBASE®, with a high mortality. Measures to improve public awareness are needed to warn potential users of the severe and sometimes fatal toxicity that may occur.


  • Tainter ML, Stockton AB, Cutting WC. Dinitrophenol in the treatment of obesity: Final report. JAMA 1935; 105:332–7.
  • Agency for Toxic Substances and Disease Registry. Toxicological Profile for Dinitrophenol. 1995.  
  • AuthenticSteroids. DNP (2,4-Dinitrophenol). 
  • Grundlingh J, Dargan P, El-Zanfaly M, et al. 2,4-dinitrophenol (DNP): a weight loss agent with significant acute toxicity and risk of death. J Med Toxicol 2011; 7:205–12. 
Follow AWTTC: