Isoniazid (also called isonicotinyl hydrazine or isonicotinic acid hydrazide); abbreviated INH or just H. Isoniazid is a first-line antituberculous medication used in the prevention and treatment of tuberculosis. IUPAC nomenclature is a systematic way of naming organic chemical compounds. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences and alloys. ... The Anatomical Therapeutic Chemical Classification System is used for the classification of drugs. ... A section of the Anatomical Therapeutic Chemical Classification System. ... PubChem is a database of chemical molecules . ... DrugBank is a database available at the University of Alberta that provides information about thousands of products. ... A chemical formula (also called molecular formula) is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... The molecular mass of a substance (less accurately called molecular weight and abbreviated as MW) is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of carbon-12). ... In pharmacology, bioavailability is used to describe the fraction of an administered dose of medication that reaches the systemic circulation, one of the principal pharmacokinetic properties of drugs. ... You may be looking for albumen, or egg white. ... Santorio Santorio (1561-1636) in his steelyard balance, from Ars de statica medecina, first published 1614 Metabolism (from μεταβολισμος (metabolismos)) is the biochemical modification of chemical compounds in living organisms anggjgjhnd cell (b). ... The elimination half-life of a drug (or any xenobiotic agent) refers to the timecourse necessary for the quantity of the xenobiotic agent in the body (or plasma concentration) to be reduced to half of its original level through various elimination processes. ... Excretion is the biological process by which an organism chemically separates waste products from its body. ... The pregnancy category of a pharmaceutical agent is an assessment of the risk of fetal injury due to the pharmaceutical, if it is used as directed by the mother. ... The regulation of therapeutic goods, that is drugs and therapeutic devices, varies by jurisdiction. ... In pharmacology and toxicology, a route of administration is the path by which a drug, fluid, poison or other substance is brought into contact with the body 1. ... Tuberculosis (commonly abbreviated as TB) is an infection caused by the bacterium Mycobacterium tuberculosis, which most commonly affects the lungs (pulmonary TB) but can also affect the central nervous system (meningitis), lymphatic system, circulatory system (Miliary tuberculosis), genitourinary system, bones and joints. ...

It is available in tablet, syrup, and injectable forms (given via intramuscular or intravenous forms), available world-wide, inexpensive to produce and is generally well tolerated.

Mechanism of action

Isoniazid is a prodrug and must be activated by bacterial catalase. The active form inhibits the synthesis of mycolic acid in the mycobacterial cell wall. A prodrug is a pharmacological substance (drug) which is administered in an inactive (or significantly less active) form. ... Mycolic acid is an acid known for protecting the cell bodies of mycobacterium, which include tuberculosis. ... Species see text Mycobacterium is the a genus of actinobacteria, given its own family, the Mycobacteriaceae. ...

Isoniazid reaches therapeutic concentrations in serum, cerebrospinal fluid (CSF), and within caseous granulomas. Isoniazid is metabolized in the liver via acetylation. There are two forms of the enzyme responsible for acetylation, so that some patients metabolize the drug quicker than others. Hence, the half-life is bimodal with peaks at 1 hour and 3 hours in the US population. The metabolites are excreted in the urine. Doses do not usually have to be adjusted in case of renal failure. Cerebrospinal fluid (CSF), Liquor cerebrospinalis, is a clear bodily fluid that occupies the subarachnoid space in the brain (the space between the skull and the cerebral cortex—more specifically, between the arachnoid and pia layers of the meninges). ... Acetylation describes a reaction, usually with acetic acid, that introduces an acetyl functional group into an organic compound. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... Bimodal can mean A bimodal distribution in statistics. ... Renal failure is the condition where the kidneys fail to function properly. ...

Isoniazid is bactericidal to rapidly-dividing mycobacteria, but is bacteriostatic if the mycobacterium is slow-growing. A bacteriocide or bactericide is a substance that kills bacteria and, preferably, nothing else. ... Species See text. ... Bacteriostatic antibiotics hamper the growth of bacteria by interfering with bacteria protein production, interfering with bacteria DNA production interfering with bacteria cellular metabolism Bacteriostatic antibiotics inhibit growth and repoduction of the bacteria, though do not kill it, while bactericidal antibiotics kill bacteria. ...

Side effects

Adverse reactions include rash, abnormal liver function tests, hepatitis, peripheral neuropathy, mild central nervous system (CNS) effects, and drug interactions resulting in increased phenytoin (Dilantin) or disulfiram (Antabuse) levels. A typical rash A rash is a change in the skin which affects its appearance or texture. ... Liver function tests (LFTs or LFs), which include liver enzymes, are groups of clinical biochemistry laboratory blood assays designed to give a doctor or other health professional information about the state of a patients liver. ... Hepatitis is a gastroenterological disease, featuring inflammation of the liver. ... Peripheral neuropathy is the medical term for damage to nerves of the peripheral nervous system, which may be caused either by diseases of the nerve or from the side-effects of systemic illness. ... A diagram showing the CNS: 1. ... Interaction is a kind of action which occurs as two or more objects have an effect upon one another. ... Phenytoin sodium (marketed as Dilantin® in the USA and as Epanutin® in the UK, by Parke-Davis, now part of Pfizer) is a commonly used antiepileptic. ... Disulfiram is a drug used to support the treatment of chronic alcoholism by producing an acute sensitivity to alcohol. ...

Peripheral neuropathy and CNS effects are associated with the use of isoniazid and is due to pyridoxine (vitamin B6) depletion, but is uncommon at doses of 5 mg/kg. Persons with conditions in which neuropathy is common (e.g., diabetes, uremia, alcoholism, malnutrition, HIV-infection), as well as pregnant women and persons with a seizure disorder, may be given pyridoxine (vitamin B6) (10-50 mg/day) with isoniazid. Peripheral neuropathy is the medical term for damage to nerves of the peripheral nervous system, which may be caused either by diseases of the nerve or from the side-effects of systemic illness. ... A diagram showing the CNS: 1. ... The two major forms of vitamin B6 are pyridoxine and pyridoxamine. ... This article is about the disease that features high blood sugar. ... Uremia is a toxic condition resulting from renal failure, when kidney function is compromised and urea, a waste product normally excreted in the urine, is retained in the blood. ... Alcoholism is the obsessive preoccupation with, alcoholic beverages to the extent that such use interferes with the drinkers normal personal, family, social, or work life, and may lead to physical, or mental harm. ... Malnutrition is a general term for the medical condition caused by an improper or insufficient (undernourished) diet. ... Human immunodeficiency virus (commonly known as HIV, and formerly known as HTLV-III and lymphadenopathy-associated virus) is a retrovirus that is the cause of the disease known as AIDS, or Acquired Immunodeficiency Syndrome, a syndrome where the immune system begins to fail, leading to many life-threatening opportunistic infections. ... A pregnant woman Pregnancy is the process by which a mammalian female carries a live offspring from conception until it develops to the point where the offspring is capable of living outside the womb. ... This article is about the medical term, epileptic seizure, as distinct from psychogenic non-epileptic seizure. ... The two major forms of vitamin B6 are pyridoxine and pyridoxamine. ...

Wikipedia links

• Tuberculosis treatment
• Tuberculosis
• Mycobacterium tuberculosis

The standard short course treatment for tuberculosis (TB) is isoniazid, rifampicin, pyrazinamide and ethambutol for two months, then isoniazid and rifampicin alone for a further four months. ... Tuberculosis (commonly abbreviated as TB) is an infection caused by the bacterium Mycobacterium tuberculosis, which most commonly affects the lungs (pulmonary TB) but can also affect the central nervous system (meningitis), lymphatic system, circulatory system (Miliary tuberculosis), genitourinary system, bones and joints. ... Binomial name Mycobacterium tuberculosis Zopf 1883 Mycobacterium tuberculosis is the bacterium that causes most cases of tuberculosis[1]. It was first described on March 24, 1882 by Robert Koch, who subsequently received the Nobel Prize in physiology or medicine for this discovery in 1905. ...

References

• Core Curriculum on Tuberculosis (2000) Division of Tuberculosis Elimination, Centers for Disease Control and Prevention

See Chapter 6, Treatment of LTBI Regimens - Isoniazid
See Chapter 7 - Treatment of TB Disease Monitoring - Adverse Reactions to First-Line TB Drugs - Isoniazid
See Table 5 First-Line Anti-TB Medications

• Isoniazid Overdose: Recognition and Management American Family Physician 1998 Feb 15