Clinical data
ATC code
Pharmacokinetic data
Elimination half-life2.5 hours
  • 5,5'-[dithiobis(methylene)]bis[4-(hydroxymethyl)-2-methylpyridin-3-ol]
CAS Number
  • 1098-97-1 ☒N
PubChem CID
  • 14190
  • 13561 checkY
  • AK5Q5FZH2R
  • D02160 checkY
  • ChEMBL488093 checkY
CompTox Dashboard (EPA)
  • DTXSID3048362 Edit this at Wikidata
ECHA InfoCard100.012.864 Edit this at Wikidata
Chemical and physical data
Molar mass368.473 g·mol−1
3D model (JSmol)
  • Interactive image
  • Oc1c(c(cnc1C)CSSCc2c(c(O)c(nc2)C)CO)CO
  • InChI=1S/C16H20N2O4S2/c1-9-15(21)13(5-19)11(3-17-9)7-23-24-8-12-4-18-10(2)16(22)14(12)6-20/h3-4,19-22H,5-8H2,1-2H3 checkY
 ☒NcheckY (what is this?)  (verify)

Pyritinol also called pyridoxine disulfide or pyrithioxine (European drug names Encephabol, Encefabol, Cerbon 6) is a semi-synthetic water-soluble analog of vitamin B6 (Pyridoxine HCl). It was produced in 1961 by Merck Laboratories by bonding 2 vitamin B6 compounds (pyridoxine) together with a disulfide bridge. Since the 1970s, it has been a prescription and OTC drug in several countries for cognitive disorders, rheumatoid arthritis,[1] and learning disorders in children. Since the early 1990s it has been sold as a nootropic dietary supplement in the United States.


It is approved for "symptomatic treatment of chronically impaired brain function in dementia syndromes" and for "supportive treatment of sequelae of craniocerebral trauma" in various European countries, including Austria, Germany, France, Italy, Portugal, and Greece. In France it is also approved for rheumatoid arthritis as a disease modifying drug, on the basis of the results of clinical trials. In many countries it is available over the counter and is widely advertised on the internet as being for "memory disturbances."[citation needed]


review refs needed

Adverse effects

Adverse effects include nausea, headache,[2] and rarely allergic reaction (mild skin reactions).[3] A 2004 survey of six case reports suggested a link between pyritinol and severe cholestatic hepatitis when on several drugs for certain diseases.[4]

Other rare side effects: acute pancreatitis[5] and photoallergic eruption.[6]

See also


  1. ^ Lemmel EM (May 1993). "Comparison of pyritinol and auranofin in the treatment of rheumatoid arthritis. The European Multicentre Study Group". British Journal of Rheumatology. 32 (5): 375–82. doi:10.1093/rheumatology/32.5.375. PMID 8495257.
  2. ^ Nachbar F, Korting HC, Vogl T (1993). "Erythema multiforme-like eruption in association with severe headache following pyritinol". Dermatology. 187 (1): 42–6. doi:10.1159/000247196. PMID 8324277.
  3. ^ de Groot, Anton C.; Nater, Johan Pieter; Weyland, J. Willem. Unwanted Effects of Cosmetics and Drugs Used in Dermatology.[full citation needed][page needed]
  4. ^ Maria V, Albuquerque A, Loureiro A, Sousa A, Victorino R (March 2004). "Severe cholestatic hepatitis induced by pyritinol". BMJ. 328 (7439): 572–4. doi:10.1136/bmj.328.7439.572. PMC 381054. PMID 15001508.
  5. ^ Straumann A, Bauer M, Pichler WJ, Pirovino M (August 1998). "Acute pancreatitis due to pyritinol: an immune-mediated phenomenon". Gastroenterology. 115 (2): 452–4. doi:10.1016/S0016-5085(98)70212-4. PMID 9679051.
  6. ^ Tanaka M, Niizeki H, Shimizu S, Miyakawa S (October 1996). "Photoallergic drug eruption due to pyridoxine hydrochloride". The Journal of Dermatology. 23 (10): 708–9. doi:10.1111/j.1346-8138.1996.tb02685.x. PMID 8973037. S2CID 28810619.

External links

  • Media related to Pyritinol at Wikimedia Commons