LD50 for human oral dose ?

[Living sucks]

Can anyone tell me from this data sheet? I only see rat, mouse and rabbit. Oral dose. And TLDO for human.

 

[Suez]

Can anyone tell me from this data sheet? I only see rat, mouse and rabbit. Oral dose. And TLDO for human.

Toxicologists can use many kinds of animals but most often testing is done with rats and mice When you are talking about safety information and in particular here you are talking about Toxicological information you are reporting on measures using tests such as the TDLO , which is The lowest dose causing a toxic effect. LD stands for "Lethal Dose". LD50 is the amount of a material, given all at once, which causes the death of 50% (one half) of a group of test animal. Im not sure what it is that your expecting to see in this information. Is it that you are looking for Human LD50 results, is that what you are looking for amongst the Toxicological info presented here?

 

[autumnal]

Can anyone tell me from this data sheet? I only see rat, mouse and rabbit. Oral dose. And TLDO for human.

LD50 is not a theoretical or estimated value, it is an experimentally-derived one. So scientist tested the chemical on those animal species and found the dose at which 50% of them died. So there will never be an LD50 given for humans, because it's obviously not ethically possible to perform that kind of testing on humans.

The lowest published toxic dose (TDLow/TDLO) is the smallest dose that has been shown to cause toxicity. Note this is only toxicity, not necessarily death. This value can exist for humans, because it can result from either experimental human tests where a dose was not thought or intended to be toxic but later turned out to be, or from confirmed hospital reports of someone taking an overdose.

What you are looking for is how to relate animal LD50 results to humans, or how to extrapolate human TDLO doses to a lethal dose. That is not my area of knowledge, however there is general information about the limitations of animal LD50 results on human predictions. To my knowledge, applying animal LD50 doses to humans gives you a very rough guide at best, plus with the risk of species-specific exceptions.

For drugs and medications, it is usually easier to browse a resource like Drugs.com which will give information on both recommended doses and overdose quantities. The overdose figures there are derived from actual real-world human events, such as case studies where someone took a given dose and died.

 

[Aap]

The only addition to the excellent post I would make is that LD50s in humans can be reported and do represent data that is not an extrapolation of animal data. For obvious reasons, this is only seen with certain compounds.

 

[autumnal]

The only addition to the excellent post I would make is that LD50s in humans can be reported and do represent data that is not an extrapolation of animal data. For obvious reasons, this is only seen with certain compounds.

Thanks for this addition. I'm curious as to what kinds of settings involve (presumably inadvertantly) giving enough of something that works out lethal to a relatively large number of subjects?

 

[Aap]

One would be intentional overdoses while another would be accidental ingestion. Unfortunately, there is a darker side with intentional human study. The Japanese (unit 731) and nazis both did this during ww2, and scientists were not just pardoned but brought to the US after the war. Likewise, the US has also dosed individuals with toxic substances (Tuskegee airmen, prisoners, Johns, and more) in the past.

 

[Living sucks]

Is it that you are looking for Human LD50 results, is that what you are looking for amongst the Toxicological info presented here?

Yes... not results but an idea or estimate

I thought it was obvious what I was asking for.
i guess I needed to say, I know what LD50 is.
i know what TDLO is. I have looked at drugs.com but the info I'm seeking isn't there. And I've looked online at other articles.
There a few people on this forum who talk about LD50 often when discussing medications, so I asked in hopes that someone might have knowledge on how LD50 might be extrapolated from the doc, if at all possible? For ex. If LD50 for a rat is xxxmg, then a human LD50 can typically be measured by 3.5x or 5x that dose. Or if TDLO is xxxmg for a human, then the LD50 is 3x or 10x that amount? (Just giving examples) and even if it's just "rough estimates".
I couldn't find anything like that in my search so I assumed it's not likely but I thought I'd pose the question to the forum to see if any of those with LD knowledge could weigh in.

i guess keeping the question short and sweet backfired.

i learned in my research that most people who die from clozapine die from bowel obstruction bcuz it's so constipating. Obviously that's at therapeutic dosages not LD. The 2nd most common cause of death at therapeutic dosage is it causes heart issues.
My heart is so weak as are my organs so I confidently feel I would not survive a lethal dose. I have 1 shot at this so I want to get the dose right even if it's 2x what I need.
i am not the normal avg healthy human body, I am near death everyday so it will take less to take me out.

Side note: I have SN but I have severe stomach and intestinal ischemia, ulcers, ulcerative colitis, crohns, celiac and so much more, so I fear my first 20-30 mins will be very painful and take longer to go unconscious and ctb. I don't want to suffer anymore. ESP my final moments.
i would love N but I'm just too limited to try to get it. I'm interested in the debreather but question it's reliability

 

[Suez]

Yes... not results but an idea or estimate

I thought it was obvious what I was asking for.
i guess I needed to say, I know what LD50 is.
i know what TDLO is. I have looked at drugs.com but the info I'm seeking isn't there. And I've looked online at other articles.
There a few people on this forum who talk about LD50 often when discussing medications, so I asked in hopes that someone might have knowledge on how LD50 might be extrapolated from the doc, if at all possible? For ex. If LD50 for a rat is xxxmg, then a human LD50 can typically be measured by 3.5x or 5x that dose. Or if TDLO is xxxmg for a human, then the LD50 is 3x or 10x that amount? (Just giving examples) and even if it's just "rough estimates".
I couldn't find anything like that in my search so I assumed it's not likely but I thought I'd pose the question to the forum to see if any of those with LD knowledge could weigh in.

i guess keeping the question short and sweet backfired.

i learned in my research that most people who die from clozapine die from bowel obstruction bcuz it's so constipating. Obviously that's at therapeutic dosages not LD. The 2nd most common cause of death at therapeutic dosage is it causes heart issues.
My heart is so weak as are my organs so I confidently feel I would not survive a lethal dose. I have 1 shot at this so I want to get the dose right even if it's 2x what I need.
i am not the normal avg healthy human body, I am near death everyday so it will take less to take me out.

Side note: I have SN but I have severe stomach and intestinal ischemia, ulcers, ulcerative colitis, crohns, celiac and so much more, so I fear my first 20-30 mins will be very painful and take longer to go unconscious and ctb. I don't want to suffer anymore. ESP my final moments.
i would love N but I'm just too limited to try to get it. I'm interested in the debreather but question it's reliability

Thats ok, I just wanted to get clarification because I think alot of people dont really understand what these terms mean and that they are actually tests that represent diagnostic values. People also dont realise that when you are talking about testing and the testing of toxicity that these are tests typically carried out on animal models and therefore you would never see human LD50 values because we dont experiment on humans, so thats why I was asking you the questions i did.
So in response to your question above to try and extrapolate from animal values, in general, if the immediate toxicity is similar in all of the different animals tested, the degree of immediate toxicity will probably be similar for humans. When the LD50 values are different for various animal species, one has to make approximations and assumptions when estimating the probable lethal dose for man.
There are a couple of Toxicity scales that are used. The two most common scales used are the "Hodge and Sterner Scale" and the "Gosselin, Smith and Hodge Scale. At the bottom of this post is Tables 1 and 2, which show the estimated lethal doses of an insecticide (called Dichlorocos) in man. What these tables do I believe is help you to be able to interpret similar information for other medication/drugs you are interested in investigating. There are special calculations used when translating animal LD50 values to possible lethal dose values for humans. Safety factors of 10,000 or 1000 are usually included in such calculations to allow for the variability between individuals and how they react to a chemical, and for the uncertainties of experiment test results.

It is also important to know that the actual LD50 value may be different for a given chemical depending on the route of exposure (e.g., oral, dermal, inhalation). For example, some LD50s for dichlorvos, an insecticide commonly used in household pesticide strips, are listed below:

• Oral LD50 (rat): 56 mg/kg
• Dermal LD50 (rat): 75 mg/kg
• Intraperitoneal LD50: (rat) 15 mg/kg
• Inhalation LC50 (rat): 1.7 ppm (15 mg/m3); 4-hour exposure
• Oral LD50 (rabbit) 10 mg/kg
• Oral LD50 (pigeon:): 23.7 mg/kg
• Oral LD50 (rat): 56 mg/kg
• Oral (mouse): 61 mg/kg
• Oral (dog): 100 mg/kg
• Oral (pig): 157 mg/kg

Differences in the LD50 toxicity ratings reflect the different routes of exposure. The toxicity rating can be different for different animals. The data above show that dichlorvos is much less toxic by ingestion in pigs or dogs than in rats. Using Table 1, dichlorvos is moderately toxic when swallowed (oral LD50) and extremely toxic when breathed (inhalation LC50) in the rat. Using Table 2, dichlorvos is considered very toxic when swallowed (oral LD50) by a rat.

Table 1: Toxicity Classes: Hodge and Sterner Scale
	Routes of Administration
		Oral LD50​	Inhalation LC50​	Dermal LD50​
Toxicity Rating​	Commonly Used Term​	(single dose to rats) mg/kg​	(exposure of rats for 4 hours) ppm​	(single application to skin of rabbits) mg/kg​	Probable Lethal Dose for Man​
1	Extremely Toxic	1 or less	10 or less	5 or less	1 grain (a taste, a drop)
2	Highly Toxic	1-50	10-100	5-43	4 ml (1 tsp)
3	Moderately Toxic	50-500	100-1000	44-340	30 ml (1 fl. oz.)
4	Slightly Toxic	500-5000	1000-10,000	350-2810	600 ml (1 pint)
5	Practically Non-toxic	5000-15,000	10,000-100,000	2820-22,590	1 litre (or 1 quart)
6	Relatively Harmless	15,000 or more	100,000	22,600 or more	1 litre (or 1 quart)

Probable Oral Lethal Dose (Human)
Table 2: Toxicity Classes: Gosselin, Smith and Hodge
Toxicity Rating or Class​	Dose​	For 70-kg Person (150 lbs)​
6 Super Toxic	Less than 5 mg/kg	1 grain (a taste – less than 7 drops)
5 Extremely Toxic	5-50 mg/kg	4 ml (between 7 drops and 1 tsp)
4 Very Toxic	50-500 mg/kg	30 ml (between 1 tsp and 1 fl ounce)
3 Moderately Toxic	0.5-5 g/kg	30-600 ml (between 1 fl oz and 1 pint)
2 Slightly Toxic	5-15 g/kg	600-1200 ml (between 1 pint to 1 quart)
1 Practically Non-Toxic	Above 15 g/kg	More than 1200 ml (more than 1 quart)

 

[Living sucks]

@Suez appreciate your feedback. I get all that and I realize they don't test LD on humans so it's not an easy answer.
i guess I'm worried about the LD for all animals being so high when there are documented reports of death in humans using 2000mg. It's confusing .

 

[Aap]

Quite simply, if you don't have a great deal of experience with the drug class and animal species, I wouldn't read anything in to LD50s for animals. You will find it varies greatly by species and receptor target. This is why human dosages can't simply be converted on a mg/kg to animals and vice versa

 

[Suez]

@Suez appreciate your feedback. I get all that and I realize they don't test LD on humans so it's not an easy answer.
i guess I'm worried about the LD for all animals being so high when there are documented reports of death in humans using 2000mg. It's confusing .

Its not an easy calculation to make. Its a gestimate at best Im afraid. And when you have so many different medical complications that need to be factored into it, things become even more complicated. Im not sure that there is any easy way around it.. Ill give it some thought anyway and see if I can look at it from a different angle. Sometimes when you look at things in ways that are maybe more unconventional or you pull things apart and take everything back to its bare structures sometimes we can surprise ourselves, who knows. That is why I became and Dr in the first place but more still why I went on a completed my PhD, that or complete stupidity. one or the other, not quite sure which :) But regards the question about LD, I asked that because you may be surprised how many people are not aware that the LD is not a human test and worse still some people are of the opinion that you can do human experimentation....so thats why I asked you to be more specific, sorry.

 

[Living sucks]

I get it with the multitude of stupid repetitive questions on a daily basis ... it becomes a normal assumption.

 

[Suez]

I get it with the multitude of stupid repetitive questions on a daily basis ... it becomes a normal assumption.

Yep your right on that one.

 

[autumnal]

One would be intentional overdoses while another would be accidental ingestion. Unfortunately, there is a darker side with intentional human study. The Japanese (unit 731) and nazis both did this during ww2, and scientists were not just pardoned but brought to the US after the war. Likewise, the US has also dosed individuals with toxic substances (Tuskegee airmen, prisoners, Johns, and more) in the past.

Damn, I was worried it might have been something to do with the Nazis...