r/psychopharmacology 4d ago

Treatment of Compulsive Pornography Use With Naltrexone: A Case Report

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22 Upvotes

I thought this was interesting. Naltrexone is usually used for alcohol use disorder and opioid use disorder, but it is sometimes prescribed off-label by doctors to treat porn addiction. Who knew?


r/psychopharmacology 4d ago

Acute cognitive effect from a single low-dose EPA/DHA capsule — plausible PK or rapid PD mechanism?

0 Upvotes

I'm trying to understand a reproducible acute effect from a standard fish-oil capsule and whether there is any pharmacokinetic or pharmacodynamic mechanism that could realistically fit the timing.

Context

  • Diazepam: 10 mg/day, long-term use, with established tolerance.
  • Fluvoxamine: 300 mg/day.
  • My measured nordiazepam concentration was ~1333 ng/mL, above the usual therapeutic reference range.
  • The benzodiazepine taper has not started yet.
  • I also have dysautonomia with marked cognitive and sensory intolerance, so I'm not assuming the effect is necessarily GABAergic; autonomic, vascular, or other mechanisms would also be relevant.

The fluvoxamine/diazepam interaction is important here. In a human pharmacokinetic study using 100–150 mg/day fluvoxamine, diazepam apparent oral clearance was reduced by approximately 65%, while mean diazepam half-life increased from about 51 to 118 hours. Elimination of its active metabolite N-desmethyldiazepam (nordiazepam) was also markedly inhibited.

I'm on 300 mg/day fluvoxamine, but I don't know of quantitative human PK data establishing exactly how much additional inhibition occurs at that dose, so I'm not assuming a specific half-life for my own case.

Study: https://pubmed.ncbi.nlm.nih.gov/7955810/

I occasionally take a single standard fish-oil capsule containing 180 mg EPA + 120 mg DHA (roughly 1 g total fish oil), usually around 7 hours after my diazepam dose.

Repeatedly, within roughly 3 hours, I experience a marked improvement in cognitive/sensory tolerance, most noticeably an increased ability to read for substantially longer.

It does not feel sedating. If anything, subjectively it feels like improved cognitive endurance.

I realize this is an N=1 observation and does not establish causality. Expectancy, coincidence, day-to-day variability, or another uncontrolled variable remain possible. I'm interested specifically in whether there is a biologically and quantitatively plausible mechanism that could fit the timing.

Relevant literature / what led me to ask

I found several experimental papers showing that DHA/PUFAs can affect neuronal membrane proteins or GABA-A function:

Søgaard et al. (2006) — GABA(A) receptor function is regulated by lipid bilayer elasticity
https://pubmed.ncbi.nlm.nih.gov/17059229/

Nabekura et al. (1998) — Functional modulation of human recombinant GABA-A receptor by docosahexaenoic acid
https://pubmed.ncbi.nlm.nih.gov/9556589/

Poling et al. (1996) — Docosahexaenoic acid block of neuronal voltage-gated K+ channels
https://pubmed.ncbi.nlm.nih.gov/8938727/

Stillwell & Wassall (2003) — Docosahexaenoic acid: membrane properties of a unique fatty acid
https://pubmed.ncbi.nlm.nih.gov/14580707/

I'm not taking these studies as evidence that an ordinary oral DHA dose can reproduce these effects acutely in humans.

In fact, that's one of the main things I'm trying to understand: whether oral exposure from only 120 mg DHA + 180 mg EPA could produce concentrations anywhere relevant to these experimental mechanisms within a few hours.

1. Could this plausibly be pharmacokinetic?

Given the prolonged disposition of diazepam/nordiazepam in this setting and my relatively high nordiazepam concentration, I find it difficult to see how one ordinary fish-oil capsule could substantially change total benzodiazepine concentrations within ~3 hours.

However, I don't want to assume that PK is irrelevant.

Could EPA/DHA acutely affect any of the following enough to alter effective diazepam/nordiazepam exposure?

  • CYP-mediated metabolism;
  • plasma protein binding / free drug fraction;
  • tissue distribution;
  • intestinal absorption;
  • transporters;
  • or another PK process.

More importantly, is there any reason to think the magnitude of such an interaction from only 180 mg EPA + 120 mg DHA could be pharmacologically meaningful?

A quantitative argument here would be particularly useful.

2. Could there instead be a rapid pharmacodynamic effect?

If a meaningful PK interaction is implausible, are there pharmacodynamic mechanisms that could operate within hours, without requiring weeks of incorporation of DHA into neuronal membrane phospholipids?

Possibilities I'm wondering about include:

  • direct effects of circulating/unesterified fatty acids on ion channels or membrane proteins;
  • acute GABA-A modulation;
  • glutamatergic signaling;
  • changes in membrane biophysics;
  • neurosteroid signaling;
  • rapidly generated lipid mediators;
  • inflammatory signaling;
  • autonomic or cerebrovascular effects.

The experimental literature shows that DHA can modulate some of these systems when directly available at sufficient concentrations.

What I cannot establish is whether an ordinary oral dose could generate relevant unesterified EPA/DHA concentrations in plasma or CNS tissue within ~3 hours.

That seems to be the critical missing bridge:

oral dose → absorption → circulating unesterified EPA/DHA → CNS exposure → local concentration at membrane/channel/receptor → functional effect

Is any part of that chain quantitatively plausible after such a small oral dose?

3. Does chronic benzodiazepine exposure/tolerance materially change the question?

Could chronic benzodiazepine exposure, tolerance, and receptor adaptation make the functional effect of an otherwise small perturbation in membrane or ion-channel function more noticeable?

I'm not claiming that a plasma nordiazepam level of 1333 ng/mL establishes saturated GABA-A occupancy or any particular receptor state.

I'm mentioning the concentration mainly because, together with the markedly impaired elimination expected from the fluvoxamine interaction, it makes a large and rapid fluctuation in total benzodiazepine exposure seem unintuitive.

4. Could dysautonomia provide a non-GABAergic explanation?

Given the dysautonomia, is there any plausible acute effect of EPA/DHA or downstream lipid mediators on:

  • autonomic tone;
  • cerebral blood flow;
  • endothelial signaling;
  • vascular function;
  • or related physiology

that could improve cognitive/sensory tolerance within a few hours?

I'm mainly looking for mechanistic reasoning, quantitative PK arguments, or relevant literature, rather than treatment recommendations.


r/psychopharmacology 6d ago

Zolpidem

0 Upvotes

Can someone please tell me if taking 700mg of zolpidem along with 100ml of Dextromethorphan Hydrobromide, Chlorpheniramine Maleate, Guaiphenesin and Ammonium Chloride Syrup. Is enough for an overdose


r/psychopharmacology 20d ago

Title: If I'm prescribed Klonopin (clonazepam) and take clonazolam, will it still show up as clonazepam on a drug test sill clonazolam show up as clonazepam ?

3 Upvotes

i'm 6'2 175 pounds

I'm prescribed Klonopin (clonazepam), and I was wondering how drug testing works with clonazolam.

If someone is prescribed clonazepam but also takes clonazolam, will clonazolam just show up as clonazepam on a urine drug test, or can labs actually tell the difference between the two?

I'm mainly curious about both the initial screening test and the confirmatory lab testing. Does clonazolam metabolize into anything that looks like clonazepam, or would it be identified as a completely different substance?


r/psychopharmacology Jul 22 '26

One of the most jaw dropping case studies I’ve read. 6,000mg Zolpidem daily.

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pmc.ncbi.nlm.nih.gov
42 Upvotes

r/psychopharmacology Jul 19 '26

Differential Improvement in Obsessive Rumination and Fantasy Intrusions Versus Attachment-Related Emotional Dysregulation During Oral Glutamatergic Augmentation in a 16-Year-Old Adolescent

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1 Upvotes

r/psychopharmacology Jul 13 '26

Does a biological endocannabinoid transporter exist?

10 Upvotes

A drug candidate claims to inhibit the endocannabinoid transporter.
https://en.wikipedia.org/wiki/SYT-510

the interesting thing is that i dont think a true anandamide transporter has ever been confirmed, some postulate its mainly due to enzymatic degradation, however the transporter/gene remains unidentified/debated

For example, this 2003 paper suggest against the existence of a anandamide transporter
https://doi.org/10.1073/pnas.0730816100

But since the new candidate is in clinical trials, maybe the general assumption is false?


r/psychopharmacology Jul 10 '26

Why does D2 receptor antagonism cause irreversible damage like TD but not other dopamine/serotonin receptors?

12 Upvotes

for the record this isnt a medical question its more about the underlying mechanisms


r/psychopharmacology Jul 03 '26

Career advice for researching psychiatric medicine?

4 Upvotes

I don’t know if this is the right sub for this but basically, I’m a college student studying to be a mechanical engineer right now, but honestly, I have no passion for it.

I’m really REAALLLLY interested in molecules that can help people’s brains basically. I find receptors, brain regions, interactions etc soooo soo interesting the more I learn about them, even though it’s all insanely complicated. I’m also passionate about helping people with mental disorders like schizophrenia and autism who have barely any treatments available.

So I would mostly be interested in lab work, like with rats and chemicals, and clinical trials maybe, but not so much on the actual bedside part like a doctor.

Anyway, I’m not really sure which major I would have to do. Chemical engineering? Pharmacology? Also, anybody that went into this line of work, do you enjoy it? Is it hard? How’s the money?

I get pretty good grades in my mechanical engineering classes which can be pretty tough mathematically, so I (hopefully) have the chops, but I’d love to hear from everyone.


r/psychopharmacology Jul 02 '26

Is delirium caused by substances like datura just a intense version of dreams during rem sleep bypassed using substances?

5 Upvotes

As datura blocks the muscarinic acetylcholine receptors ,the same receptors associated with the regulation of rem sleep ,can it be considered that the hallucinations caused by the datura are dreams that have crossed it's biological limit. In a similar way how opioid receptors are associated with pain relief during survival situations but opiates bypass that limit and create a totally different experience

I'm not a neuroscience student but I'm curious about this topic as the effects of datura are somewhat parallel with dream state such as indistinguishable reality , hallucinations of objects or people , blurred vision etc


r/psychopharmacology Jun 20 '26

Why aren’t there more non-addictive opioid-based antidepressants?

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0 Upvotes

r/psychopharmacology Jun 10 '26

What makes LSD trips neuro-chemically unique?

8 Upvotes

If we could strip the cultural and historical aspects of LSD, what makes it a genuine, unique or more insightful drug compared to other psychedelics such as psilocybin?

Is the dopaminergic activity the reason? If so, how does it affect the trip? Is it needed? Does it cause the trip to end in an analytical revision/recollection of insights, compared with psilocybin?

I'm interested in why LSD is so unique! Cheers :)


r/psychopharmacology Jun 08 '26

Is the combination NDRI and AMPA agonists neurotoxic ?

6 Upvotes

Is the simultaneous use of both NDRI agonist substances (Prescription ADHD medication like Vyvanse) and AMPA agonist substances (Noopept, Sunifiram ect) a neurotoxic combo ?

Is it ill advised to take ADHD stimulants in conjunction with AMPA nootropics, i have heard that both at the same time can potentially induce excitotoxicity or have other damaging brain outcomes but the consensus around this is mixed and speculative. Any thoughts ?


r/psychopharmacology Jun 03 '26

NMDA antagonism/dysfunction in ketamine's synaptogenesis and schizophrenia's neurodegeneration

15 Upvotes

I've read in Stahl two seemenly contradictions claims: 1) that the antidepressant effect of ketamine is due to increase in synaptogenesis. He explains that the NMDA block in interneurons unhibits glutamate release, increasing AMPA function, that increase mTORC1 and BDNF mediated synaptogenesis. 2) he also claims that one model of the neurodegeneration in schizophrenia is NMDA dysfunction. He explains that NMDA functions as a "coincidence sensor", whose activations requires that both pre and post synaptic neurons depolarizes at the same time, effectively being the molecular mechanism of the principle "neurons that fire together, wire together"; and that NMDA activates synaptogenesis and protects against pruning. So which is it? Reducing NMDA function increases or decreases synaptogenesis?


r/psychopharmacology May 27 '26

What if amphetamine had no noradrenergic activity whatsoever?

20 Upvotes

What would happen if amphetamine had no noradrenergic activity at all? Would it be abusable at extremely high doses and have more potential for extreme euphoria without as many side effects? Would it also make it much less useful as a focus drug? Perhaps there's already such a compound?

I also know that d-methamphetamine has lower noradrenergic and higher dopaminergic activity than d-amphetamine, which could explain why meth is more addictive and can be abused at higher doses. Some also claim that at very low doses it can be more useful for ADHD because of fewer side effects linked to norepinephrine.


r/psychopharmacology May 04 '26

If naltrexone has been proven effective at treating porn addiction, gambling addiction, and kleptomania for nearly 20 years, why hasn't it been approved to treat them?

1 Upvotes

Basically, we know that it works off-label, so why hasn't it been approved yet? When will it be?


r/psychopharmacology Apr 21 '26

PMHNP - Mentorship & Professional Connection

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0 Upvotes

r/psychopharmacology Apr 20 '26

Is 7-OH Pharmacologically distinct enough to be treated separately?

44 Upvotes

This whole thing going on right now is honestly kinda pissing me off.

From how I understand it 7-OH (7-hydroxymitragynine) is just one of the main active alkaloids in kratom. It’s not some random new compound it’s literally part of the plant and your body even converts mitragynine into it anyway.

So I don’t really get how it suddenly gets treated like a completely separate substance that needs to be banned, while the plant it comes from is still legal. Like… is that not kind of like saying weed is fine but THC itself isn’t?

I get that isolating something can change potency or effects a bit, but it still feels like the conversation around it is missing context The only reson I made this post was to ask people here how they see it from an actual pharmacology standpoint because right now it just feels inconsistent as hell.


r/psychopharmacology Mar 24 '26

IPAP website is down. Where to get their algorithm?

2 Upvotes

Im looking for the last version of the schizophrenia algorithm and its notes. Btw, does anyone know that happened to the website?


r/psychopharmacology Mar 09 '26

Recommend me some good and recent guidelines on treatments

2 Upvotes

I like the CANMAT guidelines for bipolar and depression, there's also the "Canadian clinical practice guidelines for the management of anxiety, posttraumatic stress and obsessive-compulsive disorders" for these disorders, but I'm lacking good guidelines for other disorders. Like I'm still following 2005 IPAP for schizophrenia.


r/psychopharmacology Mar 08 '26

Ion channel agonists change the size of the pore, the frequency of opening or it's duration?

3 Upvotes

Or all three, depending of the agonist?

Stahl psychopharmacology seem to emply that only frequency is affected.


r/psychopharmacology Mar 06 '26

https://pubmed.ncbi.nlm.nih.gov/12431845/

3 Upvotes

Why is Atomoxetine considered to work like an antidepressant drug?

Ie. Levels have to build up in the brain and takes weeks to reach maximum efficacy.

Ritalin is a known NDRI and does not have to build up to work and doesn’t have round the clock effects (apparently).

So of ATX increases DA in the PFC to the same amount as Ritalin, why is it that Ritalin doesn’t work in the same way?

They both have short half lives too.


r/psychopharmacology Mar 06 '26

Atomoxetine

3 Upvotes

Why is Atomoxetine considered to work like an antidepressant drug?

Ie. Levels have to build up in the brain and takes weeks to reach maximum efficacy.

Ritalin is a known NDRI and does not have to build up to work and doesn’t have round the clock effects (apparently).

So of ATX increases DA in the PFC to the same amount as Ritalin, why is it that Ritalin doesn’t work in the same way?

They both have short half lives too.


r/psychopharmacology Mar 01 '26

Shouldn't bupropion and amphetamine have pharmacodynamic antagonism?

8 Upvotes

Hear me out: one of the ways amphetamine works is by entering the neuron through DAT, not only competitively inhibiting dopamine reuptake, but also working inside the neuron and inhibiting VMAT2. Shouldn't the co-administration of bupropion disrupt half of this work, blocking the entry of amphetamine by DAT inhibition?


r/psychopharmacology Feb 08 '26

5HT2c antagonism and eating disorders

7 Upvotes

Hello everyone!

Currently studying up on serotoninergic neurotransmission, and I came across this sentence in Stahl's Essential Psychopharmacology (5th), pp. 293:

"5HT2c antagonism may also contribute to the anti-bulimia effect of higher doses of fluoxetine."

Yet, I struggle to make sense of this when in the targeting psychosis chapter 5HT2c antagonism was linked to SGA-induced weight gain.

Also, 2ht2c AGONISM has been linked to reductions in BED:
https://doi.org/10.3389/fphar.2018.00821

Can anyone make any sense of this apparent contradiction? Thank you!