Evidence Explorer / Evidence record
BOTANICALS & NATURAL PRODUCTS
Laetrile / amygdalin (“B17”)
No established efficacy; toxicity concern
In the NCI-described study, only one of 175 evaluable patients met response criteria; the evidence does not establish an effective cancer treatment.
MS-N006 · Sources checked October 11, 2026 · Cancer-treatment claim
What was studied?
People and setting: Patients with various advanced cancers
Evidence basis: NCI review, including a phase II study
What can we conclude?
Marketing terms such as “B17” do not make this an essential vitamin or a validated therapy.
Safety and practical context
Amygdalin can release cyanide. Serious poisoning, including death, is possible; do not use it as cancer treatment.
Questions for the care team
- Does this evidence apply to my cancer, treatment and goal?
- Does the exact preparation or delivery method match the study?
- What benefit is plausible, what could go wrong, and what care must continue?
Sources
Connected reviews
Learn how to judge a study · Return to the evidence map
This is a concise evidence brief, not an exhaustive systematic review or a personal treatment recommendation. Evidence labels describe the named use; they are not formal GRADE ratings. A missing harm report does not establish safety.
