Early Discovery Toxicology Services

Gwathmey Preclinical Testing Services, Inc. offers Early Discovery toxicology studies in small animals. Studies can be conducted under GLP or non-GLP conditions. Our dosing capabilities include oral gavages, intra-tracheal intubation, intraperitoneal, subcutaneous, intra-muscular, intravenous, intra-dermal injections, and topical administration of compounds.

Studies Offered

ACUTE TOXICITY STUDIES

These studies are conducted to determine the degree of toxicity of a compound and establish the compounds toxicity in relationship to other compounds whose acute toxicity is already known. While acute toxicity evaluates the adverse effects of a single dose, these studies can also provide information from which a mean lethal dose can be calculated. This data is helpful when designing studies of longer duration.

• Up and Down

This is used to determine dose levels. The procedure involves dosing animals one at a time: First, two animals at one dose, then another two animals one or two days later at a higher dose (if the first animals survive) or a lower dose (if the first animals die). The process will continue until the approximate LD50 has been determined, which is used to determine the mean lethal dose of compounds.

• Limit Test

Dosing with a single dose considered high enough that if no mortality or significant toxicity is seen in the animals, then no higher doses are required. Generally, 2000 mg/kg is used as the maximum dose.

• 7 Day Toxicity

Animals receive a single dose and are observed over a seven day period. After 7 days, animals are euthanized and the tissues and blood are taken for evaluation.

SHORT TERM TOXICITY STUDIES: RANGE-FINDING

After information on toxicity of a compound has been determined from acute studies, the toxic characteristics of a compound can be assessed and evaluated for possible health hazards from repeated exposure over a short period of time (7-14 days). These studies are conducted to determine the target organs for toxicity after repeated dosing. They also serve as rangefinders to predict the doses which will not cause lethality or toxicity after months or years of administration in subchronic studies.

• 14 Day Toxicity

Animals are dosed for 14 days. After 14 days, the animals are euthanized and the blood and tissues are taken and evaluated for toxicity. Gwathmey Preclinical Testing Services, Inc. provides tissue harvesting, gross, and full necropsies.