Skip Navigation
ChemIDplus A TOXNET DATABASE LiteBrowseAdvanced

Substance Name: Isoniazid [USP:INN:BAN:JAN]
RN: 54-85-3
UNII: V83O1VOZ8L
InChIKey: QRXWMOHMRWLFEY-UHFFFAOYSA-N

Note

  • Antibacterial agent used primarily as a tuberculostatic. It remains the treatment of choice for tuberculosis.

Molecular Formula

  • C6-H7-N3-O

Molecular Weight

  • 137.1413
 

Classification Codes

Classification Codes

  • Anti-Bacterial Agents
  • Anti-Infective Agents
  • Antibacterial (Tuberculostatic)
  • Antimetabolites
  • Antitubercular Agents
  • Drug / Therapeutic Agent
  • Fatty Acid Synthesis Inhibitors
  • Human Data
  • Hypolipidemic Agents
  • Mutation Data
  • Reproductive Effect
  • Skin / Eye Irritant
  • Tumor Data

Superlist Classification Code

  • Overall Carcinogenic Evaluation: Group 3

Names and Synonyms

Name of Substance

  • Isoniazid
  • Isoniazid [USP:INN:BAN:JAN]

MeSH Heading

  • Isoniazid

Synonyms

  • 4-(Hydrazinocarbonyl)pyridine
  • 4-Pyridinecarbonylhydrazine
  • 4-Pyridinecarboxylic acid, hydrazide
  • 4-Pyridinecarboxylic hydrazide
  • 4-Pyridylcarbonylhydrazide
  • 5015 R.P.
  • 5015 RP
  • AI3-23936
  • Amidon
  • Andrazide
  • Antimicina
  • Antituberkulosum
  • Armazid
  • Armazide
  • Atcotibine
  • Azuren
  • Bacillin
  • BP 5015
  • CCRIS 351
  • Cedin
  • Cedin (Aerosol)
  • Cemidon
  • Chemiazid
  • Chemidon
  • Cotinazin
  • Defonin
  • Diforin
  • Dinacrin
  • Ditubin
  • Dow-isoniazid
  • Ebidene
  • EINECS 200-214-6
  • Eralon
  • Ertuban
  • Eutizon
  • Evalon
  • Fimalene
  • FSR 3
  • FSR-3
  • Ftivazide
  • GInk
  • HIA
  • Hidranizil
  • Hidrasonil
  • Hidrulta
  • Hidrun
  • HSDB 1647
  • Hycozid
  • Hydrazid
  • Hydrazide
  • Hyzyd
  • Ido-tebin
  • Idrazide dell'acido isonicotinico
  • Idrazide dell'acido isonicotinico [Italian]
  • Idrazil
  • IN-73
  • INAH
  • INH
  • Inh-Burgthal
  • Inizid
  • Iscotin
  • Isidrina
  • Ismazide
  • Isobicina
  • Isocid
  • Isocidene
  • Isocotin
  • Isohydrazide
  • Isolyn
  • Isonerit
  • Isonex
  • Isoniazid
  • Isoniazid SA
  • Isoniazida
  • Isoniazida [INN-Spanish]
  • Isoniazide
  • Isoniazidum
  • Isoniazidum [INN-Latin]
  • Isonicid
  • Isonico
  • Isonicotan
  • Isonicotil
  • Isonicotinhydrazid
  • Isonicotinic acid hydrazide
  • Isonicotinic hydrazide
  • Isonicotinohydrazide
  • Isonicotinoyl hydrazide
  • Isonicotinoylhydrazine
  • Isonicotinsaeurehydrazid
  • Isonicotinsaeurehydrazid [German]
  • Isonicotinyl hydrazide
  • Isonicotinylhydrazine
  • Isonide
  • Isonidrin
  • Isonikazid
  • Isonilex
  • Isonin
  • Isonindon
  • Isonirit
  • Isoniton
  • Isonizide
  • Isotamine
  • Isotebe
  • Isotebezid
  • Isotinyl
  • Isozid
  • Isozide
  • Isozyd
  • L 1945
  • Laniazid
  • Mybasan
  • Neo-tizide
  • Neoteben
  • Neoxin
  • Neumandin
  • Nevin
  • Niadrin
  • Nicazide
  • Nicetal
  • Nicizina
  • Niconyl
  • Nicotibina
  • Nicotibine
  • Nicotisan
  • Nicozide
  • Nidaton
  • Nidrazid
  • Nikozid
  • Niplen
  • Nitadon
  • Niteban
  • Nitebannsc 9659
  • NSC 9659
  • Nydrazid
  • Nyscozid
  • Pelazid
  • Percin
  • Phthisen
  • Phthivazide
  • Preparation 6424
  • Pycazide
  • Pyreazid
  • Pyricidin
  • Pyrizidin
  • Raumanon
  • Razide
  • Retozide
  • Rifamate
  • Rimicid
  • Rimifon
  • Rimiphone
  • Rimitsid
  • RP-5015
  • Stanozide
  • Tubazid
  • Tubazide
  • UNII-V83O1VOZ8L

Systematic Names

  • 4-Pyridinecarboxylic acid, hydrazide
  • Isoniazid
  • Isonicotinic acid hydrazide

Superlist Names

  • Isoniazid
  • Isonicotinic acid hydrazide

Mixture Name

  • Rifater

Registry Numbers

CAS Registry Number

  • 54-85-3

FDA UNII

  • V83O1VOZ8L

Other Registry Numbers

  • 37271-10-6
  • 41466-07-3
  • 62229-51-0
  • 7640-37-1

System Generated Number

  • 0000054853

Structure Descriptors

InChI

1S/C6H7N3O/c7-9-6(10)5-1-3-8-4-2-5/h1-4H,7H2,(H,9,10)

InChIKey

QRXWMOHMRWLFEY-UHFFFAOYSA-N

Smiles

c1cnccc1C(=O)NN

Toxicity

Organism Test Type Route Reported Dose (Normalized Dose) Effect Source
cat LD50 intraperitoneal 325mg/kg (325mg/kg) LUNGS, THORAX, OR RESPIRATION: DYSPNEA

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

PERIPHERAL NERVE AND SENSATION: SPASTIC PARALYSIS WITH OR WITHOUT SENSORY CHANGE
Klinische Wochenscrift. Vol. 30, Pg. 959, 1952.
child TDLo oral 125mg/kg (125mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: COMA
Annals of Emergency Medicine. Vol. 17, Pg. 73, 1988.
child TDLo oral 195mg/kg (195mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: HEADACHE
Japanese Journal of Toxicology. Vol. 12, Pg. 225, 1999.
child TDLo oral 3600mg/kg/43W (3600mg/kg) SENSE ORGANS AND SPECIAL SENSES: OTHER: EYE

BEHAVIORAL: ATAXIA

BEHAVIORAL: TREMOR
Canadian Medical Association Journal. Vol. 148, Pg. 49, 1993.
dog LD50 oral 50mg/kg (50mg/kg)   American Review of Tuberculosis. Vol. 65, Pg. 392, 1952.
guinea pig LD50 intramuscular 255mg/kg (255mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: ATAXIA
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
guinea pig LD50 intraperitoneal 195mg/kg (195mg/kg) LUNGS, THORAX, OR RESPIRATION: DYSPNEA

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

PERIPHERAL NERVE AND SENSATION: SPASTIC PARALYSIS WITH OR WITHOUT SENSORY CHANGE
Klinische Wochenscrift. Vol. 30, Pg. 959, 1952.
guinea pig LD50 intravenous 220mg/kg (220mg/kg) GASTROINTESTINAL: "HYPERMOTILITY, DIARRHEA" Archiv fuer Toxikologie. Vol. 22, Pg. 80, 1966.
guinea pig LD50 oral 255mg/kg (255mg/kg) BEHAVIORAL: ATAXIA

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
guinea pig LD50 subcutaneous 195mg/kg (195mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: ATAXIA
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
human LDLo oral 100mg/kg (100mg/kg) PERIPHERAL NERVE AND SENSATION: STRUCTURAL CHANGE IN NERVE OR SHEATH American Review of Respiratory Disease. Vol. 105, Pg. 206, 1972.
infant TDLo oral 91mg/kg (91mg/kg) BEHAVIORAL: TREMOR

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD
Pediatrics. Vol. 95, Pg. 700, 1995.
man LDLo oral 116mg/kg (116mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

CARDIAC: OTHER CHANGES

LUNGS, THORAX, OR RESPIRATION: EMPHYSEMA
Journal of Analytical Toxicology. Vol. 16, Pg. 57, 1992.
man LDLo oral 523mg/kg/17W- (523mg/kg) LIVER: "HEPATITIS (HEPATOCELLULAR NECROSIS), DIFFUSE"

LIVER: "HEPATITIS, FIBROUS (CIRRHOSIS, POST-NECROTIC SCARRING)"
JAMA, Journal of the American Medical Association. Vol. 176, Pg. 877, 1961.
man TDLo oral 39mg/kg/9D-I (39mg/kg) SKIN AND APPENDAGES (SKIN): "DERMATITIS, OTHER: AFTER SYSTEMIC EXPOSURE" Southern Medical Journal. Vol. 75, Pg. 81, 1982.
man TDLo oral 100mg/kg/3W-C (100mg/kg) BEHAVIORAL: ANOREXIA (HUMAN

SKIN AND APPENDAGES (SKIN): SWEATING: OTHER

KIDNEY, URETER, AND BLADDER: OTHER CHANGES
American Review of Respiratory Disease. Vol. 106, Pg. 849, 1972.
man TDLo oral 430mg/kg (430mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: GENERAL ANESTHETIC
Neurology. Vol. 20, Pg. 299, 1970.
mouse LD50 intramuscular 137mg/kg (137mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

LUNGS, THORAX, OR RESPIRATION: DYSPNEA
American Review of Tuberculosis. Vol. 65, Pg. 376, 1952.
mouse LD50 intraperitoneal 100mg/kg (100mg/kg)   National Technical Information Service. Vol. AD277-689,
mouse LD50 intravenous 149mg/kg (149mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD Journal of Pharmacology and Experimental Therapeutics. Vol. 122, Pg. 110, 1958.
mouse LD50 oral 133mg/kg (133mg/kg) LUNGS, THORAX, OR RESPIRATION: DYSPNEA

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD
American Review of Tuberculosis. Vol. 65, Pg. 376, 1952.
mouse LD50 subcutaneous 125mg/kg (125mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD Yakugaku Zasshi. Journal of Pharmacy. Vol. 81, Pg. 1225, 1961.
rabbit LD50 intracrebral > 12mg/kg (12mg/kg) BEHAVIORAL: ATAXIA

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
rabbit LD50 intramuscular 155mg/kg (155mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: ATAXIA
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
rabbit LD50 intraperitoneal 147mg/kg (147mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: ATAXIA
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
rabbit LD50 intravenous 94mg/kg (94mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD American Review of Tuberculosis. Vol. 65, Pg. 376, 1952.
rabbit LD50 oral 250mg/kg (250mg/kg)   Arzneimittel-Forschung. Drug Research. Vol. 12, Pg. 22, 1962.
rabbit LD50 subcutaneous 135mg/kg (135mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: ATAXIA
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
rat LD50 intramuscular 400mg/kg (400mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD Therapie. Vol. 8, Pg. 62, 1953.
rat LD50 intraperitoneal 335mg/kg (335mg/kg) BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

BEHAVIORAL: ATAXIA
Schweizerische Zeitschrift fuer Tuberkulose und Pneumonologie. Vol. 9, Pg. 226, 1952.
rat LD50 intravenous 365mg/kg (365mg/kg)   Arzneimittel-Forschung. Drug Research. Vol. 26, Pg. 409, 1976.
rat LD50 oral 1250mg/kg (1250mg/kg)   Arzneimittel-Forschung. Drug Research. Vol. 26, Pg. 409, 1976.
rat LD50 subcutaneous 329mg/kg (329mg/kg)   Journal of Pharmacology and Experimental Therapeutics. Vol. 119, Pg. 444, 1957.
women TDLo oral 12mg/kg/2D-I (12mg/kg) BEHAVIORAL: ATAXIA

BEHAVIORAL: TOXIC PSYCHOSIS
Neurology. Vol. 34, Pg. 703, 1984.
women TDLo oral 90200ug/kg/7D (90.2mg/kg) BEHAVIORAL: SOMNOLENCE (GENERAL DEPRESSED ACTIVITY)

BEHAVIORAL: HEADACHE

CARDIAC: EKG CHANGES NOT DIAGNOSTIC OF ABOVE
Pediatrics. Vol. 97, Pg. 782, 1996.
women TDLo oral 99300ug/kg (99.3mg/kg) BEHAVIORAL: "HALLUCINATIONS, DISTORTED PERCEPTIONS"

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD

GASTROINTESTINAL: NAUSEA OR VOMITING
Pediatrics. Vol. 95, Pg. 700, 1995.
women TDLo oral 11250mg/kg (11250mg/kg) BEHAVIORAL: COMA

LUNGS, THORAX, OR RESPIRATION: RESPIRATORY STIMULATION

BEHAVIORAL: CONVULSIONS OR EFFECT ON SEIZURE THRESHOLD
Anaesthesia. Vol. 47, Pg. 781, 1992.

Physical Properties

Physical Property Value Units Temp (deg C) Source
Melting Point 171.4 deg C   EXP
pKa Dissociation Constant 1.82 (none) 20 EXP
log P (octanol-water) -0.7 (none)   EXP
Water Solubility 1.40E+05 mg/L 25 EXP
Vapor Pressure 4.64E-05 mm Hg 25 EST
Henry's Law Constant 1.21E-14 atm-m3/mole 25 EST
Atmospheric OH Rate Constant 5.84E-12 cm3/molecule-sec 25 EST

Physical property data is provided to ChemIDplus by SRC, Inc.