Mellanby effect. Can it explain some effects of benzodiazepines?

[Renald]

Mellanby effect is the phenomenon responsible for the more sober subjective feeling when our BAC is decreasing comparing to the same BAC level when the concentration of alcohol in blood was increasing. Briefly, you can feel approximately the same alcohol effects with the BAC of 0.5 permille when you just began drinking and with BAC of 1.0 permille when you stopped drinking and your alcohol concentration is lowering.

An old article about this issue:

http://www.icadtsinternational.com/files/documents/1977_025.pdf

I want to discuss about can this effect be responsible for subjective feelings we get when using benzos? Alcohol and benzos both act on GABAa system, and maybe this is the explanation we usually feel most from the benzodiazepine in first hours after its usage even if it is clonazepam, diazepam or other very long acting drug.

 

[Solipsis]

Does tachyphylaxis not account for this effect?

 

[Renald]

Possibly yes. I was always curious about why I feel quite sober even when my BAC-tester show 0.8-1.0 on declining but intoxicated on 0.5 when I begin to drink. Not a long ago I found this phenomenon. Surely, this is some kind of tachyphylaxis, and I want to discuss, can it be used to explain benzo-related effects?

 

[Solipsis]

You would have to be more precise in your question... but generally I think that tachyphylaxis is something intrinsic to pharmacology, but more pronounced with some drugs - like I think especially the high potency/efficacy or high-to-full agonist types.