Chemicals / Complex Chemical Agents/ Chemical:
Zidovudine 

INFORMATION AVAILABLE

GENERAL CHEMICAL INFORMATION THERAPEUTIC INFORMATION [DOSE, FREQUENCY & ROUTE]

NUTRITIONAL INFORMATION

TOXICITY INFORMATION ENVIRONMENTAL INFORMATION
Information in this page has been entered to support the current volumes of Wildpro and further information will be added as new volumes are completed. This page is not intended to substitute for the manufacturer's data sheet and the information is not yet complete for all species, or for all contra-indications etc.

CAUTION: Before any pharmaceutical product is used, the manufacturer's data sheet, containing information on uses, dosage and administration, contra-indications, warnings etc., should always be consulted. It is important to remember that licensing of pharmaceutical products for use in a particular species/condition, as well as mandatory meat and milk withdrawal times for food-producing animals, varies between countries and changes with time. Withdrawal times also may vary between different pharmaceutical formulations and depending on route of administration. In Europe the prescription cascade must be followed. In the USA FARAD may be consulted regarding residues and meat and milk withdrawal times.

General Chemical Information

Summary 
Thymidine analogue, commonly known as AZT, used in the treatment of HIV infection.

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Names and Formulae
Type Nucleoside analogue (nucleoside reverse transcriptase inhibitor, NRTI). (B567.99.w99)
Alternative Names Azidothymidine, AZT, ZDV,  RetrovirŪ, BW A509U. (B567.99.w99, J549.30.w1) 3'-azido-3'-deoxythymidine, (B567.99.w99) 3'-azido-2',3'dideoxythymidine. (J549.30.w1)
Chemical Formula 3'-azido-3'-deoxythymidine; it contains a 3'-azido group instead of a 3'-hydroxyl group. (B567.99.w99)
Chemical Structure --
Molecular Weight --
Related Chemicals --

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Physical Properties / Chemistry
Appearance

White crystalline solid. (B567.99.w99)

Melting point 119-121 °C. (B567.99.w99)
Boiling point --
Density --
Water solubility 20 mg/mL. (B567.99.w99)
Other solubility --
Acid/Base --

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Pharmacology & General Information
Pharmacology Converted to mono-, di- than triphosphate form by cellular phosphorylase enzymes. AZT triphosphate is incorporated into viral DNA chains at the 3' end by viral reverse transcriptase, terminating the chain. (B567.99.w99, J549.30.w1)
Storage / Stability --
Legal Category (In UK) --

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References

Associated Techniques

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ORGANISATIONS

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ELECTRONIC LIBRARY
(Further Reading)
Click image for full contents list of ELECTRONIC LIBRARY

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Authors Debra Bourne MA VetMB PhD MRCVS (V.w5)
Referees --

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Therapeutic Information

Uses/Indications
Activity
  • Active against retroviruses, notably HIV. (B567.99.w99)
  • Active against HIV-1 and HIV-2. (J549.30.w1)
Appropriate Use
  • For the treatment of adult humans with HIV-1 infection and reduced immunity indicated by CD4+ lymphocyte count below 55/ml, treatment of children over three months old infected with HIV and with reduced immunity, treatment of pregnant women infected with HIV (to prevent maternal-fetal transmission), and in combination with zalcitabine for treating adults infected with HIV-1 and with CD4+ count below 300.mL. (B567.99.w99)
  • In the treatment of HIV infection. (J549.30.w1)
Limitations
  • Not active against Herpesvirus hominis (simplex) Virus, Varicella-Zoster Virus, vaccinia or human cytomegalovirus. (B567.99.w99)
  • In patients undergoing prolonged therapy, isolates resistant to AZT have been isolated. (B567.99.w99)
  • AZT-resistant mutations of HIV develop, mainly at six codons in the pol gene of HIV which encodes reverse transcriptase. Some of the mutations boost the resistance caused by other mutations but do not cause resistance by themselves. Multiple mutations are needed for high-level resistance. (B560.14.w14)
Notes --

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Pharmacokinetics and Drug Interactions
Absorption /Bioavailability
  • Oral bioavailability 65% due to first pass metabolism. (B567.99.w99)
Distribution
  • Crosses the blood-brain barrier. (B567.99.w99)
Plasma Protein binding / Storage --
Elimination Route
  • Mainly by conjugation in the liver followed by excretion; metabolism is probably limited by hepatic blood flow. (B567.99.w99)
  • About 14% excreted unchanged following oral administration. (B567.99.w99)
Elimination half-life / Clearance Rate
  • Dose-independent kinetics with intravenous administation at 1.0 - 5.0 mg/kg or oral dosing of 2.0 - 10.0 mg/kg. (B567.99.w99)
  • Rapidly removed: total body clearance 1,900 mL/min. (B567.99.w99)
    • Clearance may be reduced if hepatic blood flow is reduced. (B567.99.w99)
Drug Interactions --

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Administration
Formulations available Capsules containing 100 mg; also intravenous and syrup formulations. (B567.99.w99)
Doses / Administration Routes / Frequencies
  • 100 mg every four hours, orally. (B567.99.w99)
  • Orally, 600 mg/day (two 300 mg tablets). (J549.30.w1)
Monitoring parameters --

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Withdrawal period / Withholding time
Notes --

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Toxic Information

Toxic effects of Pharmaceutical Products
Contraindications / Precautions
  • Contraindicated for use in patients showing severe, life-threatening reaction. (B567.99.w99)
Adverse Effects / Side Effects / Warnings
  • Because AZT is converted to AZT-TP in practically all dividing cells, toxicity is a problem, particularly bone marrow suppression leading to anaemia and neutropaenia. (B560.14.w14)
  • Haematological effects: leucopaenia, neutropaenia, anaemia, due to dose-dependent suppression of bone marrow (degree of effect is modified by the individual's bone marrow reserve). (B567.99.w99)
  • Headache, insomnia and myalgia may occur. (B567.99.w99)
Operator Warnings --
Overdose / Acute Toxicity --

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Detailed Toxicological Information
Classification --
Acute Toxicity --
Chronic Toxicity --
Reproductive effects
  • In rats and rabbits, embryotoxicity has been observed. (B567.99.w99)
Teratogenic effects --
Mutagenic effects --
Carcinogenic effects
  • In rats and mice, vaginal carcinomas have been observed following chronic high dosing. (B567.99.w99)

Organ toxicity --
Bird Toxicity --
Aquatic organism activity --
Other organism toxicity --

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Nutrient Information

Nutritional Data
Sources --
Biological Use --
Recommended Daily Allowance / Recommended level in food --
Stability in food (Storage time) --
Interactions --

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External / Environmental Information

External / Environmental Uses
Use --
Formulation --
Application method --
Application Concentration --
Persistence of Effect / Frequency of Application --

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Sources in the Environment
Natural sources --
Human-associated sources

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Effects on the Environment
Effects in the aquatic environment

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Effects on land --

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Persistence in the Environment
Breakdown in soil and groundwater

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Breakdown in water --
Breakdown in vegetation --

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