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Biotech / Medical : PFE (Pfizer) How high will it go? -- Ignore unavailable to you. Want to Upgrade?

To: Stockjet who wrote (798)	3/29/1998 9:01:00 PM
From: Jerry Olson	Read Replies (2) \| Respond to of 9523

HI Stockjet Hey how about our PFE<VBG> Geez that was terrific news huh??? Listen FWIW...forget the markets "noise"...buy any dips in this stock..it has excellent support at 84... just continue to add to your position...AND HOLD!!!! When the numbers start to flow into the coffers of this Co... PFE will become the Biggest Drug Co. in the world... Remember, the market is forward looking...the dollars that will go to the bottom line of PFE for years to come will make their earnings explode...And Stockjet...with all the hype YET to come???? He he he Keep your shorts on<g>...

To: Stockjet who wrote (798)	3/29/1998 11:37:00 PM
From: Zebra 365	Read Replies (2) \| Respond to of 9523

<<How will grapefruit juice affect a man who uses Viagra?>> Many drugs are deactivated in the liver. In this case think of the liver as a factory in reverse (like a "chop shop" for stolen cars), it disassembles Sildenafil molecules into another molecule (which still has some effect, 50%) and then disassembles that molecule into something that has no effect (that is then eliminated in the urine (13%) or feces (80%). In healthy young volunteers this process eliminates 50% of the drug in 4 hours (and 25% in the next four hours, and 12.5% in the next four hours) Theoretically after 12 hours you would still have 12.5% of the drug in your system, and it would be effectively gone after 24 hours (six half lives). Healthy elderly (>65) volunteers cleared silldenafil less than the younger ones, resulting in plasma levels 40% higher at the same dose. In someone drinking grapefruit juice or eating a grapefruit, this factory line could be as much as 90% shut down. This could increase the half-life by ten-fold, i.e. a factory working at 10% capacity takes 10 times as long to produce as much. If this then extended the half-life by 10-fold it would become fourty hours instead of four, then the dose you take on Tuesday is still mostly around when you take a dose on Wednesday and has additive effect. (PFE recommends no more than one dose per 24 hour period.) As side effects increased with dosage in the reported studies (plasma levels) this would likely increase the side-effects (and desired effects) of the drug. Exactly to what extent I cannot say. As I mentioned, this grapefruit effect on this enzyme system, has only recently been discovered and is now being studied. Most drugs known to use this enzyme system are now having grapefruit warnings added to their label material. PFE warns about ketoconazole type drugs and other "inhibitors of these isoenzymes" with Viagra but did not mention grapefruit. They did try giving 100mg a day to someone at the same time that person was taking a normal dose of erythromycin. This resulted in sildenifil 182% higher levels. Erythromycin is nowhere near as powerful an inhibitor of this enzyme system as grapefruit. Tagamet (800mg) given with a single 50mg dose of Viagra, caused a 56% increase in plasma concentration of Viagra in healthy volunteers (age not given) Elderly people already have reduced activity of this system, couple that with an AM grapefruit, and that dose of Viagra, you see my point? My main point is that people often think of drug-drug interactions but often little attention is given to drug-food interactions. The grapefruit effect on certain drugs is one of the more important drug-food interactions yet discovered. I suspect PFE will add it to the label material soon. With all the hype that Viagra gets, it would be an excellent chance to increase general awareness (among both physicians and patients) of this newly discovered grapefruit interaction. (Now I'm probably kicked off the mailing list for the Texas Ruby Red Grapefruit people. I love those, have some in the fridge right now and send them for Xmas gifts, see why I have to use a pseudonym!) Zebra P.S. I do not think this applies to all citrus fruit, only grapefruit as far as has been reported.