Pondimin (fenfluramine) 
Author Message
 Pondimin (fenfluramine)

fenfluramine had been implicated in brain damage and that the FDA
was looking into it.
Any info, anyone?


Fri, 01 Nov 1996 11:27:52 GMT
 Pondimin (fenfluramine)

Quote:

>fenfluramine had been implicated in brain damage and that the FDA
>was looking into it.
>Any info, anyone?

Check your distribu8tion line in the original posting, it's apparently
got part of your intended text -- reference to a broadcast on this
subject?  (Unless it's *my* newsreader screwing up :-)

A check of the Magazine Index at the local library will turn up some
cautionary info on fenfluramine, including Lancet editorials about
fenfluramine; I recall that ritalin was safest, fenfluramine did some
damage, and 'ecstasy' did more damage in rat brains.

Not clear whether there's a longterm problem but the caution is that
as people get older and lose brain cells, anything lost previously
can become revealed -- we may have a few extra but can't risk using
them up early on drug damage.

I started readig up on fenfluramine after reading an article by
Wurtman in Scientific American, Dec. '89 on Carbohydrates and Depression.
Wurtman's company Interneuron was testing the drug I think, and it's
being tried in a pure D- and L- isomer.  Old "Pondimin" weight loss
fenfluramine drug is a mixture of the two isomers.



Wed, 06 Nov 1996 21:58:50 GMT
 Pondimin (fenfluramine)

Quote:


>>fenfluramine had been implicated in brain damage and that the FDA
>>was looking into it.
>>Any info, anyone?
>Check your distribu8tion line in the original posting, it's apparently
>got part of your intended text -- reference to a broadcast on this
>subject?  (Unless it's *my* newsreader screwing up :-)

>A check of the Magazine Index at the local library will turn up some
>cautionary info on fenfluramine, including Lancet editorials about
>fenfluramine; I recall that ritalin was safest, fenfluramine did some
>damage, and 'ecstasy' did more damage in rat brains.

ritalin is a dopaminergic amphetamine...  i haven't looked into the
neurotoxicity of ritalin, but comparisons between seritonergic and
dopaminergic {*filter*} could be abused...  also, i don't think we're at
the stage where you can usefully state that fenfluramine or MDMA does
more/less damage, unless it is *quite* *clearly* stated in what
model and what doses you're using.

Quote:
>Not clear whether there's a longterm problem but the caution is that
>as people get older and lose brain cells, anything lost previously
>can become revealed -- we may have a few extra but can't risk using
>them up early on drug damage.

this is a theory.  its *far* from proven.

in fact, 5-HT neurotoxicity from agents such as MDMA and fluoxetine at
reasonable human dose levels is far from proven -- see O'Callighan's article
in NIDA #136 on GFAP assays for neurotoxicity...

there are other possibilities, such also such as neurotoxicity being
an agent which produces 5-HT neuroplasticity ("Azmitia" in AU, "seritonergic"
and "giant" in SUB should pull this article up in medline)

--

"And then the alien anthropologists - Admitted they were still perplexed - But
on eliminating every other reason - For our sad demise - They logged the only
explanation left - This species has amused itself to death" -- Roger Waters



Sat, 09 Nov 1996 15:38:18 GMT
 Pondimin (fenfluramine)
i'm passing the following information along from an authoritiative
friend who prefers to remain anonymous:

Date: Tue, 24 May 94 16:07:14 -0500
From: [a well-known medicinal chemist]

Interneuron is awaiting FDA approval to market Dexfenfluramine through
Lederle Laboratories in the U.S.  It is big in Europe, but the expertes seem
to think it doesn't work that well.  Studies showing it caused very modest
weight loss (6-8 lbs?) were coupled with a stringent dietary regimen.  There
are no studies to show that it works in people who eat their normal diet.
Even so, Interneuron is a venture capital start up company, and the market
for diet aids in the U.S. is HUGE.

Fenfluramine does cause long-term 5-HT neuronal changes (in rats).  See a
paper by Johnson and Nichols, Pharmacology biochemistry and Behavior, Vol 36,
pp 105-109, 1990.  10 mg/kg of Dfen produced long-lasting changes.  A single
10 mg/kg dose of MDMA will not do this in rats.

Interestingly, although Dfen produces long-term deficits in brain levels of
5-HT, its metabolite 5-HIAA, and the biosynthetic enzyme tryptophan hydroxylase
as well as in the number of 5-HT uptake sites, Interneuron, and the French
parent company Servier claim that the neurons are "okay", they just don't have
any serotonin, any synthesis capacity, or the ability to take it up from the
synapse.  hmmm....  I guess you can't expect otherwise, or you'd be marketing
a diet aid that changed your brain structure, and you'd make no money on that.

By the way, studies of postmortem brains from auto accidents have shown that
while dopamine neurons decrease in number with age, serotonin neurons do not.
So the aging problem shifts the balance to serotonin and the loss of 5-HT
neurons while young may not show up later.  This may be a problem that only
really occurs with dopamine, which is pretty toxic stuff.

Of course we all know that amphetamine releases dopamine, and is a psycho-
stimulant, while fenfluramine, which releases 5-HT makes you feel full and
lethargic.  It makes you wonder about mental acuity in later years if the
serotonin system is there full-bore, but the dopaminergic system is dying!



Mon, 11 Nov 1996 14:13:10 GMT
 Pondimin (fenfluramine)

Quote:

>This may be a problem that only
>really occurs with dopamine, which is pretty toxic stuff.

I wasn't aware of any excitotoxicity from dopamine itself.  The
neurotoxic effects of amphetamine are, I think, hypothesized to occur
from a metabolite of dopamine along a pathway that only becomes
significant when large amounts of it are{*filter*} around in the
synaptic cleft (e.g., from amphetamines).  I saw one article that
showed that OH-DOPA was not the excitotoxin in question (and can
dig it up on request).

--

|  44 Canterbury, Athens OH  45701  | finger for PGP2.2 block                 |
|  SCA: Erasmus Marwick, Dernehealde Pursuivant, Dernehealde, Middle Kingdom  |



Tue, 12 Nov 1996 04:00:00 GMT
 
 [ 5 post ] 

 Relevant Pages 

1. Pondimin (fenfluramine)

2. Pondimin (fenfluramine) 40 mg tablet and obtaining pharmiceuticals in Mexico.

3. Phentermin and Pondimin

4. Pondimin/Ionamin weight loss treatment

5. Pondimin,Ionimin

6. Pondimin,Ionimin

7. Pondimin/Fastin

8. PME Ionamin and Pondimin

9. Phentermine and Pondimin Diet- Safe???

10. Ionamin&Pondimin for Weightloss

11. FASTIN, PONDIMIN &PHENTERMINE

12. Paxil and Pondimin taken together??


 
Powered by phpBB® Forum Software