24. Toxicology Flashcards
What is toxicology?
Study of adverse effects of chemicals
What happens in an acute toxicity study?
Administration of a single dose
Monitored for 14 days
Determine outcome
Choose a non-toxic dose
What happens in a subacute study?
Repeated dosing
14 days
Estimate a dose for subchronic studies
What happens in a subchronic study?
Up to 90 days
High dose, intermediate dose and low dose given
What happens in a chronic study?
Lasts 3 months to 2 years
Study carcinogenicity
Control group
What is a lethal dose?
Death is the endpoint
What is NOAEL?
No Observed Adverse Effect Level
Highest dose that doesn’t cause a statistically significant toxic response
What is LOAEL?
Lowest Observed Adverse Effect Level
Lowest dose that generates a statistically significant toxic effect
What is a reference dose?
Assumed to be safe for the human population when taken daily
NOAEL divided by uncertainty factors
What is the maximum recommended starting dose?
Starting dose for human clinical trials
NOAEL HED/safety factor
What is the human equivalent dose?
Animal dose adjusted on basis of body surface area
What is the therapeutic index?
The difference between toxic and effective dose
What is the Ames test?
Salmonella is mutated so it can’t synthesise histidine
If the drug mutates gene back it proves mutagenicity
How is genotoxicity tested?
Gene mutations to bacteria
IV test for chromosome damage to mammal cells
Live test for chromosomal damage to rat haemopoietic cells
