What is the typical duration of a subchronic toxicity test?

What is the typical duration of a subchronic toxicity test?

• A. 28 days (1 month)
• B. 13 weeks (3 months)
• C. 26 weeks (6 months)
• D. 52 weeks (1 year)

Answer: (B)

Subchronic toxicity testing examines the effects of repeated exposure over an intermediate period, long enough to reveal cumulative or mid-term toxicity but not so long as to be considered chronic. The standard duration for this type of study is about 90 days, which is roughly 13 weeks. This timing is used in regulatory guidelines (such as OECD Guideline 408 for a 90-day study in rodents, and 409 for dogs) and in practice to observe potential organ toxicity, weight changes, and laboratory parameter shifts after repeated dosing. Shorter durations, like 28 days, are used for subacute assessments, while longer durations (26 weeks or 52 weeks) are associated with chronic exposure studies. Therefore, the typical duration of a subchronic toxicity test is about 90 days, or 13 weeks.

Subchronic toxicity testing examines the effects of repeated exposure over an intermediate period, long enough to reveal cumulative or mid-term toxicity but not so long as to be considered chronic. The standard duration for this type of study is about 90 days, which is roughly 13 weeks. This timing is used in regulatory guidelines (such as OECD Guideline 408 for a 90-day study in rodents, and 409 for dogs) and in practice to observe potential organ toxicity, weight changes, and laboratory parameter shifts after repeated dosing. Shorter durations, like 28 days, are used for subacute assessments, while longer durations (26 weeks or 52 weeks) are associated with chronic exposure studies. Therefore, the typical duration of a subchronic toxicity test is about 90 days, or 13 weeks.