U.S. doctors online nowAsk doctors free
A 32-year-old member asked:

i have never understood how ld50 is very confidence inducing? has the medical profession ever considered raising that standard?

2 doctor answers4 doctors weighed in
Dr. Donald Stewart
Family Medicine 41 years experience
The : The ld50, which is the dose of a substance that will result in death of 50% of the people who take it, is not really a medical term. It is a term from the science of toxicology. In medical use, it is a way judging the relative safety of a medication. Generally, a physician would want to prescribe a medication with a therapeutic dose that was as much lower than its ld50 as possible.. Most substances, even water, can kill people if taken at a high enough dose. The ld50 is simply a way of looking at the relative safety, or danger, of a substance.
Dr. Ed Friedlander
Pathology 44 years experience
The LD50 is of course only one of a host of numbers we look at to determine whether something is safe. I appreciate your question and your concern about safety of the medicines you take. It would be misleading at best to suggest that LD50 is central to anybody's calculations of an appropriate dose for a medication.
Mar 12, 2013
Dr. Dan Fisher
Internal Medicine 27 years experience
See below.: We have all grown accustomed to using it as it is. It works clinically and "better" is not always better. For example would an LD 20 or LD 90 be more useful? There is no incentive to change because it is good enough.

90,000 U.S. doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more. Get help now:

Ask doctors free
Personalized answers
Free
Talk to a doctor
24/7 visits
$15 per month

90,000 U.S. doctors in 147 specialties are here to answer your questions or offer you advice, prescriptions, and more. Get help now:

Ask doctors free
Personalized answers
Free
Talk to a doctor
24/7 visits
$15 per month
Last updated Oct 3, 2016
Connect with a U.S. board-certified doctor by text or video anytime, anywhere.
24/7 visits
$15 per month

Disclaimer:

Content on HealthTap (including answers) should not be used for medical advice, diagnosis, or treatment, and interactions on HealthTap do not create a doctor-patient relationship. Never disregard or delay professional medical advice in person because of anything on HealthTap. Call your doctor or 911 if you think you may have a medical emergency.