Acute toxicity studies are preclinical studies conducted to assess the potential toxic effects of a drug or other substance after a single exposure or a short-term exposure. These studies are usually conducted in laboratory animals, such as rats, mice, rabbits, or dogs, before testing the substance in humans.

The primary objective of acute toxicity studies is to determine the dose at which a substance causes adverse effects, such as death or serious illness, and to establish a safe starting dose for further studies. The studies are usually conducted using a variety of routes of administration, including oral, intravenous, and dermal, to evaluate the toxicity of the substance under different conditions.

Acute toxicity studies typically involve the use of a single dose of the test substance, and animals are observed for a defined period of time for any signs of toxicity, including changes in behavior, clinical signs, and gross and microscopic pathology. The results of these studies are used to calculate the LD50, which is the dose of the substance that causes lethal effects in 50% of animals.

In addition to the LD50, acute toxicity studies may also provide information about the target organs and systems affected by the substance, as well as the dose-response relationship and the potential reversibility of the toxic effects.

Overall, acute toxicity studies are an important part of preclinical safety assessment, providing essential information about the potential risks and safety of a drug or other substance. However, it is important to note that the results of acute toxicity studies should be interpreted with caution and in conjunction with other toxicity data, as the effects observed in animals may not necessarily predict the effects in humans.