Uh-Oh… I really know how to start a thread that makes a bad impression huh?
I am behind on my replies to this, so yeah, huge block of text again. You don’t have to read it all, or any of it, but there is no way to make it shorter.
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Firstly, IM needles, here are a mass of links to research.
http://www.bd.com/hypodermic/pdf/Intramuscular_Injection_Guidelines.pdf - Says that while 1 – 1 ½ inch needles are appropriate for adult IM injections, needle lengths up to 3” may be required for large adults. It also states that the dorsogluteal site should be avoided in obese adults.
Another study,
http://www.bmj.com/content/332/7542/637 , finds that blue and green needles do not reach the gluteal muscles “in a considerable number of patients”, finding that…
Due to the depth of fat, intramuscular injections with large (green) needles into the anterior gluteal site in this sample would be subcutaneous in 12% of patients (16% of women and 5% of men), and for injections with smaller (blue) needles in 26% (36% of women and 10% of men). In the posterior gluteal site, large needles will fail to reach muscle in 43% (57% of women and 21% of men), and small needles will fail in 72% (90% of women and 44% of men)… In highly obese populations, the depth could be expected to be even greater than that shown here.
As previous studies have shown low efficacy of gluteal intramuscular injections, this route should be avoided for most drugs. If alternative routes are not possible, using longer needles should be considered.
And
http://www.nursingtimes.net/nursing...on-based-on-research-evidence/1952004.article
“Needle length and tissue depth are linked to adverse events as obesity has increased. Patients should be weighed and assessed for the required needle length with needles inserted up to the hub to ensure the full length is used. Recommendations for longer needles included – 25mm for women weighing between 60–90kg and 38mm for women who weigh over 90kg to penetrate the deltoid muscle (Poland et al, 1997).
Current DH (2006) recommendations are that needle length must be sufficient to penetrate the subcutaneous fat layer using at least 25mm (23 gauge) blue needles or 38mm (21gauge) green needles for adults. For children 16mm is recommended, although decisions depend on other factors such as age and subcutaneous fat. Recent studies have recommended calculating patients’ BMI to assist assessment of body fat (Nisbet, 2006).
”
And;
http://www.ncbi.nlm.nih.gov/pubmed/17484745
“Mean subcutaneous tissue thickness at the dorsogluteal site was 34.5 mm for overweight adults, 40.2 mm for obese adults and 51.4 mm for extremely obese adults, and at the ventrogluteal site was 38.2 mm for overweight adults, 43.1 mm for obese adults and 53.8 mm for extremely obese adults.
CONCLUSION:
Intramuscular injections administered at the dorsogluteal site in 98% of women and 37% of men, and at the ventrogluteal site in 97% of women and 57% of men, would not reach the muscles of the buttock. A needle longer that 1.5 inches should be used in women whose body mass index is more than 24.9 kg/m2, the dorsogluteal site may be used in all overweight and obese men, and the ventrogluteal site may be used in overweight men only.”
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Right, on to replies to posts in this thread…
That is not true though. I never said it wasn't a factor at all, I said it was very negligible. Tolerance has 90% to do with it. …
If you were dosing two people for the first time with a drug like heroin or oxy for example, your assumption that the larger person required double the dose from your example, could end up killing them. A heavier person might need a marginally fractional bigger dose, but it is not even close to direct proportion of double the weight, double the dosage. …
When you go to get on suboxone or methadone, the doctors don't give a crap how much you weigh or how big you are. Their dosage reccomendations have nothing to do with weight or body size. They base them on tolerance.
This may be true of methadone, I have no knowledge, but it certainly isn't true of all drugs. For example, prescribed doses of opiates and anesthetics change for the very overweight. See:
http://bja.oxfordjournals.org/content/105/suppl_1/i16.full for just the first example from Google. It discusses the way that the pharmacokinetic (PK) and pharmacodynamic (PD) properties of some drugs are different in the morbidly obese body than in a lean one. The obese body is different/disordered enough in functioning that prescribing some drugs to morbidly obese patients requires not just extra caution, but additional knowledge. That article also pretty clearly says that doses of anaesthetics are normally given based on total body weight, but that this can be unsuitable with obese patients, because you risk giving them a massive OD. As you say, you can't just double the dose for double the weight. That article is actually full of fascinating stuff and warrants a read. See sample;
article said:
"After a single bolus dose, thiopental is rapidly distributed from the plasma to the peripheral tissues. The decline in plasma concentration and termination of effect is because of rapid redistribution of thiopental to peripheral tissues. The high lipophilicity of thiopental increases its apparent volume of distribution and elimination of half-life in obese subjects. ]Total clearance is increased two-fold in the obese vs normal weight subjects. However, when normalized to TBW, there was no difference in clearance. Obese individuals have an increased cardiac output when compared with normal weight subjects, and cardiac output is an important determinant in the early distribution kinetics of i.v. drugs.8 Simulations of the effects of alterations in blood flows and body composition associated with MO showed a 60% decreased peak plasma thiopental concentration after a 250 mg dose when compared with normal weight subjects.26 Thiopental plasma concentrations were also decreased up to 2 h after administration. Thiopental induction doses adjusted to LBW resulted in the same peak plasma concentrations as dose adjusted to cardiac output. These data suggest that administering induction doses based on LBW is appropriate. However, the increased cardiac output can result in a more rapid redistribution of thiopental from the effect site into the plasma, resulting in more rapid awakening after a single bolus dose."
"According to the ASA closed claims database, 48% of adverse respiratory events secondary to opioids were in obese or MO individuals.35 Increases in cardiac output and changes in body composition (increases in fat and lean mass) associated with MO alter the PK properties of opioids."
"Anaesthetizing MO individuals requires careful considerations regarding changes in the PK and PD properties of numerous drugs used in anaesthesia. Physiological and anthropometric changes, such as increases in cardiac output, changes in regional blood flow, and increases in fat mass and lean mass affect PK properties. In addition, respiratory pathophysiology such as the increased incidence of OSA, and fat deposition in the oropharynx and chest wall alter PD properties of anaesthetics.
Dosing scalars other than TBW must be considered when administering drugs to MO individuals. Administering drugs based on TBW can result in an overdose, while administration based on IBW can result in a subtherapeutic dose. With the exception of the non-depolarizing neuromuscular-blocking agents (where IBW might be appropriate), LBW is the most appropriate dosing scalar for the majority of anaesthetic agents including opioids and anaesthetic-induction agents, especially as cardiac output is significantly correlated to LBW, except in individuals with obesity cardiomyopathy.
The incidence of MO continues to increase, and anaesthesiologists are increasingly exposed to MO subjects presenting for various procedures. Knowledge of changes in PK and PD properties that occur in MO subjects and careful consideration of the optimal dosing scalar is necessary for safe and effective administration of anaesthesia in this patient population."
See also;
http://ceaccp.oxfordjournals.org/content/4/5/152.full
article2 said:
"One of the many problems in providing anaesthesia for morbidly obese patients is the influence of obesity on pharmacokinetics and pharmacodynamics. Drug administration in obese patients is difficult because recommended doses are based on pharmacokinetic data obtained from individuals with normal weights; therefore, mistakes in the determination of the appropriate dose are often made. Because of comorbidity in these patients, the function of organs involved in drug elimination (e.g. kidney, liver) can be affected making pharmacokinetics more difficult and complex. ...
Our present knowledge of the influence of obesity on drug pharmacokinetics is still limited or confused by concomitant pathophysiological disorders. In these cases, close pharmacodynamic monitoring is essential in order to titrate anaesthetic drug administration towards the desired clinical effect.
It has been observed that most anaesthetists reduce doses in obese patients based on experience and intuition alone. However, a better knowledge of pharmacokinetics might improve drug titration."
So, it seems, science is just beginning to catch up to this one.
Also, I have to admit, the direction I did NOT see the data going was that obese people may often require LOWER doses of drugs than their healthy counterparts.
It only proves that tolerance is a BIGGER factor than weight, not the only factor.
Imagine two IDENTICAL people, except one weighs 100kg the other one 200kg. In theory the 200kg person should require twice the dose to reach the same effects, if that means nothing to you, so be it, for most people it means a lot. If they were both highly tolerant to said drug, the heavier one would still need twice the dose, it doesn’t change.
It seems to depend what you're using, but yes, for a frequent recreational drug user, tolerance would generally be the main factor. But main is not the same as only, and many drug users do not use often, so tolerance is almost a non-issue for a lot of the drug-using population. Also, as stated, it seems that sometimes, fat people require LESS drugs.
In your country the BBWs are probably sought after, it is a sign of wealth and ability to bear many children.
Also, some people like a challenge.
I don't think I'm much of a challenge. Actually, to be fair, I jest at my un-rapeable-ness, but my weight has never interfered with my ability to get laid consensually, so I don't know why I assume I'd find it such an unthinkable scenario that I may get assaulted unwillingly
OP, I think in the end you could just preface any HR questions by saying "oh, btw, I'm seriously overweight if that makes a difference"
I personally take my weight into account when thinking about drug use and HR. However, I'm not sure everyone would think to. Particularly in the UK, weight is considered such a touchy subject that we are afraid to even bring up someone’s obesity. People don't bring their own weight up. Never mind obesity, we don't really talk much about body mass at all unless someone is particularly tiny or massive, and sure not to be offended.
Aw don't say that Bb gurl.
I would absolutely assault you if you were passed out.
Bring a wheelbarrow, throw ya in it, take you to my country and marry you.
Where we could both smoke tons of meth and make terrible posts on bluelight together
That actually sounds like a lot of fun. But I'm standing strong on this one; this thread isn't terrible. Wrong time, wrong place, wrong approach, perhaps, but not terrible. Normally I'd have backed down by now and accepted the community judgement of a bad thread, but I just don't feel it this time.
Maybe I should print out your post and stick it to my bathroom mirror, recite it like a mantra to give me the confidence to feel assaultable, each and every day.
To be honest, OP you are clearly an intelligent person, I like your writing style but like most other people I see no point in this thread. I simply don't know what to discuss, there is nothing to agree nor disagree with. Except maybe one thing:
Dose required may not be proportional directly to weight but it is proportional to blood volume. Fat people tend to have more blood than skinny. It is true that tolerance can cause bigger dose differences than body weight but both are factors. Just because a 90lb girl can drink more 3 times more than a 200lb guy does not mean weight is not a factor.
Edit: A normal sized person has between 4.5L and 5L (about 8.5 pints). For every additional kilogram (2 pounds) of weight, blood volume goes up by a little over 1% (60 ml, or 2 fluid ounces)..
Blood volume - thanks! This was one of those 'key terms' I was missing!
And yes, it seems this threat has been poorly received all round. But I still think it was a valid thing to bring up, since it seems the medical community is just getting into real research regarding, and actually beginning to implement, changing practices for obese patients.
TL;DR
What is the topic here exactly? The title intrigued me but I didn't feel like reading the long OP.
I saw something about fat people requiring larger doses and that's just not true. Tolerance is the only real factor that has anything to do with dosage, which is what explains 5'4" 90lb girls I know who can drink most 6'5" 200lb guys under the table or shoot 3 bundles a day of H.. Size and weight have basically zero to do with the dosage of drugs you can ingest.
As the linked articles above mention, size and weight DO have an impact on ideal drug doses, for some drugs, and often in unexpected directions. If this is true for medical use, it would stand to reason that it may be true of some recreational drug use as well.
If I truly didn't want a friend using a certain drug, I simply wouldn't use it around them and would refuse to watch them do it in my presence. Sounds controlling, but to me it's just common courtesy. There are people who drink in front of recovering alcoholics and such, which I think is terribly selfish. I can't tell another adult what to do, but I'm not gonna be a part of it. (Then again, I don't inject things or do "heart attack" drugs like cocaine, so it doesn't really apply).
Thanks. You actually wrote the kind of response I initially asked for, and I like the way you simply group risks together.
I think you could do drugs, but while avoiding ones that could be problematic. Would you really want to take stimulants like amphetamine, meth or mdma with a massive weight problem?
I think weed, benzos, opiates, and some psychedelics might not be too risky, however.
In my experience as a very-very-fat-person, or VVFP, amphetamine was fine, ditto benzos, weed, and most psychedelics, though 6-APB messed with my circulation more than I have seen it mess with other peoples' circulation. Cocaine always makes my chest hurt so I just don't bother. MDMA, the main issue I ran across is that it's hard to enjoy it because of sweating! Fat people are sweaty. Eeew.
And, according to those articles, at least, opiates are more dangerous for the overweight, which stands to reason.
Yeah, it's really a downside that you can't see the veins!
Well, yeah, but jabs and jibs aside, the same way a junkie who destroys their veins may be met with sarcasm when complaining about difficulty registering, fat people who use IV drugs actually do face new risks, even just related to finding a vein, and poking fun won't alter their increased risk of injury.
Saw an earlier post about weight versus intoxication, and I dont know whose side Im supporting but. My grandma weighs probably close to 350 pounds and she gets blown off just 0.25mg, to the point she has "hangovers" (which I assume is some light cloudiness). Thats just a half of a half of a football... Literally alprazolam crumbs.
Im 190 and the only time I ever remember being "hungover" off Xanax was after eating several mgs at once and blacking out.
Also my sister is about 130 pounds and can drink more than most men when she gets down, and she rarely even drinks. Perhaps being from a long line of alcoholics has something to do with it. Ive seen her smash several 40s in a night and maintain like a champ. I have 60 pounds on her, and I black out after 2 if I drink them that fast.
True that. Different drugs affect different people, well... differently! Some people just naturally have a ludicrous alcohol tolerance, or seem to arrive at benzo's needing addict-strength doses. Equally, some people have crazy low thresholds for certain drugs. I have a friend who really will enter a k-hole on a bump. I've never understood it, and have always been jealous.
