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The following message was posted to: PharmPK
Hello All! I have been following the discussion on water consumed
during oral drug administration and have a related question of my own.
How does water consumption affect food intake? In order to improve
urinary output we are planning on the subjects taking about 720 mL of
water in two portions 60 and 30 minute prior to dosing. How would this
impact their appetite?
I saw Manoj K. Paruthi's reply indicating that the volume should not
cross 300mL as this change the state to 'Fed'. I was wondering whether
their are any references that could help me understand this better.
Thanks,
Rajeev
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The following message was posted to: PharmPK
Dear Manoj,
I am also very curios to see any abstract/article on the 300 mL water
akin
to 'FED' state - even transiently with regards to bioavailability of a
drug.
Thanks,
Chandra Chaurasia
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Hi All
As many of you will know, I have spent much of my working career
evaluating the impact of GI Physiology on drug absorption / formulation
behaviour etc.
Sadly I have to tell you that it is an "old wives tale" that relatively
"small" volumes of water can switch the stomach from fasted to fed
mode. My gastroenterologist colleagues have estimated it would take
over a 1000ml bolus fluid ingestion in man to have an "outside chance"
of changing the stomach motility pattern. In simple terms the ingested
volume has to distend the stomach to a great degree to create a sham
fed emptying pattern. In addition don't forget that in the fasted
state water leaves the stomach with a half life (T50%) of circa 12 to
15mins.....
I hope this helps...
Ian Wilding
Pharmaceutical Profiles
Mere Way
Ruddington Fields
Ruddington
Nottingham
UK
NG11 6JS
Tel: + 44 115 974 9000
Fax: + 44 115 974 8000
E-mail : iwilding.-a-.pharmprofiles.co.uk
www.pharmprofiles.com
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The following message was posted to: PharmPK
Dear All,
I think unknowingly I have raised something very sensitive. In fact
this was one of the comments made by some professor involved with MRI
studies to study the fate of dosage forms after administration. In one
of the studies a formulation designed to stay longer in the stomach,
stayed longer when administered with relatively large volumes of cold
water and since the drug incorporated had window of absorption it
affected the bio availability. For dosage forms designed to release the
drug quickly, this may or may not affect.
I really apologies if I have raised some confusions.
Regards
Manoj K. Paruthi
Manager, R&D
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The following message was posted to: PharmPK
Rajeev wrote asking about drinks of water over 300 ml.
For about 15 years at the University of Surrey we have been using 500
ml of
water or dilute (10%) glucose 'meals" as standard when measuring gastric
emptying by bio-impedance so we have done many dozens if not hundreds of
them and published papers on GLP-1, calorie load and appetite. One test
of
500 ml water has no effect at all on appetite while there certainly is a
reduction when the liquid meal contains enough calories. When I was
developing the method I found that when one 500 ml water meal follows
another with just a comfort break between them, the emptying rate of the
second is the same as the first. Accordingly, I think the idea that
300ml
reduces appetite must relate to calorific drinks and not water itself so
Rajeev can give his 2 x 360 ml without having any effect on appetite.
I am curious to know why he asks the question.
Andrew Sutton
Andrew Sutton, MBBS, MD(London), FFA
Guildford Clinical Pharmacology Ltd.
The Technology Centre, Occam Road
Guildford, Surrey, UK. GU2 7YG
Tel: +44 (0)1483 455375. Direct: 688303
Mobile +44 (0) 7770 820 145 (To 5pm EST)
URL: www.gcpl.co.uk
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The following message was posted to: PharmPK
Manoj,
Personally I thought the discussion thread was very good and I would
guess a lot
of people took some new knowledge away with them - or at least they had
to
question their own views and how they had arrived at them. Thank you.
Dave
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Copyright 1995-2010 David W. A. Bourne (david@boomer.org)