The estimated LD-50 (lethal threshold) for marijuana,established in 1988 by the DEA’s appropriate fact-finder, is 1:20,000 or 1:40,000.
“At present it is estimated that marijuana’s LD-50 is around1:20,000 or 1:40,000. In layman terms this means that in order to induce death a marijuana smoker would have to consume 20,000 to 40,000 times as much marijuana as is contained in one marijuana cigarette. NIDA-supplied marijuana cigarettes weigh approximately .9 grams. A smoker would theoretically have to consume nearly 1,500 pounds of marijuana within about fifteen minutes to induce a lethal response.
Note: In Judge Young’s report cannabis is referred to as marijuana
UNITED STATES DEPARTMENT OF JUSTICE
Drug Enforcement Administration
In The Matter Of
Docket No. 86-22
MARIJUANA RESCHEDULING PETITION )
OPINION AND RECOMMENDED RULING, FINDINGS OF
FACT, CONCLUSIONS OF LAW AND DECISION OF
Administrative LAW JUDGE.
FRANCIS L. YOUNG, Administrative Law Judge
DATED: SEP 6 1988
FRANCIS L. YOUNG, Administrative Law Judge
ACCEPTED SAFETY FOR USE UNDER MEDICAL SUPERVISION
With respect to whether or not there is “a lack of accepted safety
for use of [marijuana] under medical supervision”, the record shows the
following facts to be uncontroverted.
Findings of Fact
Point 3. The most obvious concern when dealing with drug
safety is the possibility of lethal effects. Can the drug
4. Nearly all medicines have toxic, potentially lethal
effects. But marijuana is not such a substance. There is no
record in the extensive medical literature describing a
proven, documented cannabis-induced fatality.
5. This is a remarkable statement. First, the record on
marijuana encompasses 5,000 years of human experience.
Second, marijuana is now used daily by enormous numbers of
people throughout the world. Estimates suggest that from
twenty million to fifty million Americans routinely, albeit
illegally, smoke marijuana without the benefit of direct
medical supervision. Yet, despite this long history of use
and the extraordinarily high numbers of social smokers,
there are simply no credible medical reports to suggest
that consuming marijuana has caused a single death.
6. By contrast aspirin, a commonly used, over-the-counter
medicine, causes hundreds of deaths each year.
7. Drugs used in medicine are routinely given what is
called an LD-50. The LD-50 rating indicates at what dosage
fifty percent of test animals receiving a drug will die as
a result of drug induced toxicity. A number of researchers
have attempted to determine marijuana’s LD-50 rating in
test animals, without success. Simply stated, researchers
have been unable to give animals enough marijuana to induce
8. At present it is estimated that marijuana’s LD-50 is
1:20,000 or 1:40,000. In layman terms this means that in
order to induce death a marijuana smoker would have to
consume 20,000 to 40,000 times as much marijuana as is
contained in onemarijuana cigarette. NIDA-supplied
marijuana cigarettes weigh approximately .9 grams. A smoker
would theoretically have to consume nearly 1,500 pounds of
marijuana within about fifteen minutes to induce a lethal
9. In practical terms, marijuana cannot induce a lethal
response as a result of drug-related toxicity.
10. Another common medical way to determine drug safety is
called the therapeutic ratio. This ratio defines the
difference between a therapeutically effective dose and a
dose which is capable of inducing adverse effects.
11. A commonly used over-the-counter product like aspirin
has a therapeutic ratio of around 1:20. Two aspirins are
the recommended dose for adult patients. Twenty times this
dose, forty aspirins, may cause a lethal reaction in some
patients, and will almost certainly cause gross injury to
the digestive system, including extensive internal
12. The therapeutic ratio for prescribed drugs is commonly
around 1:10 or lower. Valium, a commonly used prescriptive
drug, may cause very serious biological damage if patients
use ten times the recommended (therapeutic) dose.
13. There are, of course, prescriptive drugs which have
much lower therapeutic ratios. Many of the drugs used to
treat patients with cancer, glaucoma and multiple sclerosis
are highly toxic. The therapeutic ratio of some of the
drugs used in antineoplastic therapies, for example, are
regarded as extremely toxic poisons with therapeutic ratios
that may fall below 1:1.5. These drugs also have very low
LD-50 ratios and can result in toxic, even lethal
reactions, while being properly employed.
14. By contrast, marijuana’s therapeutic ratio, like its
LD-50, is impossible to quantify because it is so high.
15. In strict medical terms marijuana is far safer than
many foods we commonly consume. For example, eating ten raw
potatoes can result in a toxic response. By comparison, it
is physically impossible to eat enough marijuana to induce
16. Marijuana, in its natural form, is one of the safest
therapeutically active substances known to man. By any
measure of rational analysis marijuana can be safely used
within a supervised routine of medical care.”