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Pupils cease to dilate with extended/heavy drug use

fairnymph

fairnymph

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While this is not the case with me personally, I have observed that in the cases of my husband and others, their pupils no longer dilate in response to various stimulatory drugs (phenethylamine class, including hallucinogens). In some cases there is simply no dilation (meth, amph, MDMA) and in other cases only minor dilation (2c compounds, for ex). Whereas during initial usage of these drugs, there was full blown pupil dilation.

Has anyone else noticed/experienced this, and any thoughts on the reason why?
 
How frequent was the drug use in the instances of halted dilation? If the use was frequent enough, the receptors affected may have been downregulated. That's all I can think of....
 
This is my thinking too, downregulation.

In terms of frequency, anywhere from 2 days a week to every day, depending on the drug. Probably some cross effects too (i.e. meth addiction leading to loss of dilation on other related drugs).

I'm thinking there must be others who have noticed this on bl.
 
Down-regulation would explain acute effects... i.e. up to the next week maximum, but longer than that, it would have to be something else... long term use of beta receptor agonists causes cadiomyopathy in the form of an enlarged heart, so it's possible that you get chronic changes in the ciliary muscle... but I really don't know...
 
It just doesn't seem likely, you can induce things like in vitro, with saturating concentration of agonists for weeks, but even like chronic dosing of massive doses of classical receptor agonists, it only takes like a ~72 hours...

Here are some studies using irreversible antagonists, and hence, near complete receptor knock down (though fairly, it is a different method of receptor inactivation).

http://jpet.aspetjournals.org/cgi/reprint/257/2/608 Half-life for recovery 170 and 70 hours

http://www.ncbi.nlm.nih.gov/entrez/..._uids=6324006&query_hl=19&itool=pubmed_DocSum 0.4 to 1.6 days.

Of course I'm not going to say it's impossible, but it just seems really unlikely.
 
BilZ0r said:
Down-regulation would explain acute effects... i.e. up to the next week maximum, but longer than that, it would have to be something else... long term use of beta receptor agonists causes cadiomyopathy in the form of an enlarged heart, so it's possible that you get chronic changes in the ciliary muscle... but I really don't know...
Click to expand...

I think chronic changes in ciliary muscle responsivity to prolonged acute adrenergic stimulation are a likely hypothesis for the loss of mydriasis. Has he ever checked to see if there is a transient dilation during the initial onset of the drug that then quickly fades away?
 
No transient dilation.

I view it as a sign of damage (however you define that), I guess it's a question of where this damage is. IOr loss of responsivity, which I consider 'damage'.

Still, no one else has observed this effect? I'd like to know how widespread it is with heavy users. Maybe I should ask in OD. I've never heard of the reverse happening in opiate users (ie pupils ceasing to contract), which would support both theories.
 
I began taking dextroamphetamine daily just under a week ago, and I'm beginning to notice a similar effect, which is interesting given that my pupils are particularly prone to hyperdilation (yay for night vision!). I usually experience very, very prolonged dilation after taking any stimulants, but as of today my pupils are much smaller than they were initially. I'm gonna have to look into this...
 
I'm the same way, very prone to hyperdilation and I also have excellent night vision. My pupils are naturally dilated more than most people (which sucks, I can't wear opaque coloured contacts), people are always asking me if I'm high. I've always wondered if it's linked to my naturally high strung/stimulated state, personally. Eyes fascinate me...

What dose of dex are you taking? I fear daily amphetamine use. Did you try methylphenidate first?
 
I was prescribed dex first because of low incidence of GI disturbance. I have IBS and I'm very sensitive to stimulants. This is definitely a short term stint, and i'm only prescribed 5-15 mg a day. I started developing some severe attention deficit problems most likely as a result of recent psychiatric trauma, and it's exam time... I'm sure you get the picture. My shrink is most intent on getting me through exams without destroying my grades and making me freak the fuck out...

I'll try to keep track of my pupil dilation for the next few days, and then perhaps I'll save some for later in the summer and see if my typical dilation returns after abstaining for a while.
 
fairnymph said:
I'm the same way, very prone to hyperdilation and I also have excellent night vision. My pupils are naturally dilated more than most people (which sucks, I can't wear opaque coloured contacts), people are always asking me if I'm high.
Click to expand...

I get this all the time, too! However, I never get any indication of this at the workplace, which makes me scared to go there while under the innfluence :(
 
^^ Ah well, at least big pupils make y'all look hot.

There are just so many unknowns. Sure 5-HT2 receptors cause pupil dilitation[1], but is that was neccesarily causes the dilation? Especially during amphetamine usage.

There are all kinds of, effects that could be going on. Serotonin can enhance parasympathetic activity [2].

Chronic beta- adrenoreceptor stimulation could lead so hypertrophy of ciliary muscles... who knows?


I mean, obviously, you've got a chronic, semi-permanent change in receptor function, just what receptor it is, and via what mechanism the receptor function has changed, is the unknown.
 
I too experience no pupil dilation more often than not after ingesting methamphetamine and/or MDMA.

This has only recently, last 3 months, been noticed. I've been a regular user for around 18 months.

I thought I was the only one!

:)

Ashley.
 
kittyinthedark said:
I was prescribed dex first because of low incidence of GI disturbance. I have IBS and I'm very sensitive to stimulants. This is definitely a short term stint, and i'm only prescribed 5-15 mg a day. I started developing some severe attention deficit problems most likely as a result of recent psychiatric trauma, and it's exam time... I'm sure you get the picture. My shrink is most intent on getting me through exams without destroying my grades and making me freak the fuck out...

I'll try to keep track of my pupil dilation for the next few days, and then perhaps I'll save some for later in the summer and see if my typical dilation returns after abstaining for a while.
Click to expand...

I have had IBS-D the last 10 years after getting very sick in India.

All stimulants increase the pain for my IBS - caffiene, nicotine, amphetamines, reboxetine, psuedo epherdrine, ect.

Cause i take Dex every day for my ADD i have to take Immodium every 2nd day which really helps reduce the pain, and 2 Ibuprofen every day which is probably not good for my stomach, but i will not just ' put up with the pain' as some people tell me (a few selfish doctors)

60mg of Codiene and 1000mg of Paracetalamal totally stops the pain, but i try to keep it to once a week, cause i love Codiene way too much and find it very 'moreish'.

Also I take Propranalol (beta1 and beta2 blocker) at night if the pain is too great from excessive stimualants because it blocks Beta2 receptors on your sensory neurons in your gut. I have found that Beta1 blockers (like Atenalol) do NOT stop the pain from stimualants, but do slow the heart down which is nice.
 
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i dunno what the defining attribute is that causes some people to be more suseptable to pupil dialation but if i even ingest a tylenol mine blow up like two pennies its kind of humorous really.
 
lildevildiablo said:
i dunno what the defining attribute is that causes some people to be more suseptable to pupil dialation but if i even ingest a tylenol mine blow up like two pennies its kind of humorous really.
Click to expand...

You might want to actually test that. It's probably a placebo reaction. Flash a light in your eyes afterwards and I'll bet you get normal constriction.




Okay, now on the other hand: why is there no tolerance to miosis with opioid use?
 
BilZ0r said:
Down-regulation would explain acute effects... i.e. up to the next week maximum, but longer than that, it would have to be something else... long term use of beta receptor agonists causes cadiomyopathy in the form of an enlarged heart, so it's possible that you get chronic changes in the ciliary muscle... but I really don't know...
Click to expand...

At one time, I was dropping acid everyday. The first day, my eyes were fully dilated. The next day and on, I would double the previous dosage, but my eyes didn't dilate at all..although I was tripping (a little).

This month, I was rolling for 3 days in a row. My eyes were fully dilated for these 3 days.

I'm not sure why it's different, but I sure am interested to find out.
 
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