Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
The TD50, or Therapeutic Dose 50, refers to the dose at which 50% of individuals experience therapeutic effects from a drug or treatment. It helps determine appropriate dosages for medical purposes.
Related terms
ED50 (Effective Dose): The ED50 represents the dose at which 50% of individuals experience desired therapeutic effects from a drug or treatment.
Maximum Tolerated Dose (MTD): MTD refers to the highest dose of a drug or treatment that can be administered without causing unacceptable side effects.
Therapeutic Index: The therapeutic index is the ratio between the toxic dose and the therapeutic dose of a drug, indicating its safety margin.