what 5-ASA have you tried?

[ErinD]

Well i have been a week on the 20 mg or prednisone with favorable results. I called my GI to give him the update and waiting for him to call me back with the next step. Last week he had mentioned if the week went well he was going to add Asacol to the 20mg for another week, then taper the pred again as long as that went ok.

I was previously on Asacol when first diagnosed and at the time it did help some, but not enough as i was in too much of a flare. It seems that most people have been on Asacol, does anyone have any experiences with any of the other 5-ASA's? I guess i just wonder why docs seem to gravitate to Asacol most of the time. I'm thinking of asking about Pentasa but i don't know if anyone has actually tried it. Lialda sounds too new...they only show safety in use up to 6 weeks and i know this is going to be a long term maintenance drug for me so i don't want those unknowns...

any thoughts would be great!

[mini]

Hi Erin

So great to hear you are doing really well and the predisone has worked well for you

Hmm wish I could answer your question but, pretty soon I could be in the same situation looking for something to maintain remission now I have come off the Entocort (day 4 so far so good). I guess this is a thread we will both need to keep up to date.

Once again so happy to hear things are going good for you.

[tex]

Hi Erin,

My guess is that the folks who promote Asacol are probably willing to give doctors more perks than the competition offers, in order to persuade them to prescribe their product. That's apparently why many products are prescribed over others, and why they continue to be prescribed, even after reports of serious problems begin to surface among patients. As always, money talks, and so do vacation trips, (and "medical seminars", which are often held on tropical resort islands).

In the case of Asacol over Pentasa for the treatment of UC, though, there's another consideration. Asacol is "encapsulated", (enteric-coated), so that it does not normally become available until it reaches the lower third of the small intestine, (the ileum), and the colon, whereas Pentasa uses another activation mechanism, (sustained-activation), so that it begins to become available, (to a slight degree), as soon as it reaches the duodenum, and it becomes progressively more available as it proceeds down the GI tract. Since UC is primarily active in the distal end of the colon, (the sigmoid colon and below), many doctors probably believe that Asacol will be likely to deliver medication to the preferred target area more effectively than Pentasa. If you look at the actual way that Pentasa is activated, though, it should deliver the active ingredient to the preferred target area quite effectively. In either case, only a relatively small amount of the active ingredient is absorbed, anyway, (less than 30 %, normally)

Also, this is just a guess, but Asacol may have been around longer, and that can sometimes be an advantage, as doctors become "comfortable" with a med. It was approved in 1992, I believe, but I have no idea how long Pentasa has been around. Lialda sounds promising, but as you mention, it received FDA approval only a little over 14 months ago. It's manufactured by the same company that makes Pentasa, (Shire plc).

Tex

[ErinD]

Hi Tex!
Thanks for the info on Asacol vs. Pentasa...one thing i am concerned about is my tummy. I am usually sensitive to meds and a lot of them will make me sick to my stomach. Do you think that the Pentasa being dissolved in the duodenum may lead to more nausea than the Asacol? Honestly, i would like to try Pentasa as it seems to have less scary side effects than the Asacol but that is my main concern...
what are your thoughts?

[tex]

Hi Erin,

Back in February, I posted a more detailed description of how the various branded 5-ASA medications deliver the active ingredient to the GI tract. Here's a copy of that post, in case you're interested:

This topic, (about the Asacol capsules passing through the GI tract and remaining intact, sometimes), comes up on this board every once in a while, so here's the "poop" on that phenomenon:

In order to insure delivery of the active 5-ASA compounds to the ileum and the colon, (without becoming activated in the stomach, or upper small intestine), the ingredients are encapsulated in a "shell" made of acid-resistant acrylic resin, used in combination with sodium bicarbonate/glycine buffering. Two different types of commercial resins are used for the various 5-ASA products, (which include Asacol, Pentasa, Rowasa, Colazal, etc.). The resin used for Asacol is known in the trade as Eudragit S, and the one used for the others is Eudragit L. Eudragit S disintegrates at pH>7, (IOW, a pH value greater than 7, which would be a slightly alkaline level), whereas Eudragit L disintegrates at approximately a pH value of 6, (which would be a slightly acid level). Obviously, a pH value of 6 would be reached sooner than a pH value of 7, as the capsules travel down the GI tract. The pH of the stomach should be somewhere in the 2 to 3 range, (assuming the stomach is producing sufficient acid for proper digestion), and as the chime leaves the stomach, the pancreas dumps bicarbonate into the small intestine, (at the upper duodenum), in order to raise the pH level of the chime as it passes through the intestines.

Therefore, I would surmise that if the pH of your ileum and colon are acidic, (that is, pH below 7), the Asacol capsules will not disintegrate, and should pass through the entire system, in their original form.

If the capsules disintegrate, (IOW, if the pH is greater than 7), then the sulfasalazine parent ingredient will be reduced by the bacterial enzyme azoreductase, to the active ingredients, sulfapyridine, (which is effective to treat rheumatoid arthritis), and 5-ASA, (which is effective to treat colitis). IOW, coliform bacteria are necessary to reduce the relatively inactive parent drug to its active derivatives.

I would further surmise that in the absence of adequate coliform bacteria, (IOW, an inadequate supply of the bacterial enzyme azoreductase), then the conversion will not take place, (the components will not be split and activated), and no benefit will be derived from the drug, even though the capsule might have disintegrated correctly.

Pentasa uses a different technology - it is microencapsulated in a semipermeable ethylcellulose membrane, which is acid stable, and active 5-ASA diffuses through the membrane at a rate that is dependent on the ambient pH. With this system, the time to 50% release at a pH of 2 is 15 hours, whereas at a pH of 7, the time is 4 to 5 hours. IOW, not much will be released in the stomach, and the rate of release will increase as the med travels farther down the GI tract.

Colazal uses a completely different mechanism - it uses one 5-ASA molecule linked to an inert unabsorbed carrier molecule. Colazal is sometimes effective for patients who get no benefit from the other 5-ASA drugs. It still requires the presence of colonic bacteria, however, in order to activate the 5-ASA. Therefore, I would assume that if a patients gut bacteria are in disarray, then the 5-ASA meds may be ineffective.

It's no wonder then, that Asacol does not work for everyone, since the pH of the intestines needs to be in the proper range for the encapsulation to disintegrate, and the colonic bacteria need to be producing the enzyme azoreductase, in order for the 5-ASA to become activated. It would appear that this family of meds would work properly on someone with a normal digestive system, (which none of us have), but it may be ineffective for those of us with the noted digestive system problems. At least that's the way I see it.

Tex

If your stomach is producing enough gastric acid, (hydrochloric acid), to digest food, then the pH should be low enough that very, very little mesalamine should be released in the stomach from Pentasa, (since the stomach usually empties out within two to fours after eating). In fact, the normal pH range of the contents of the stomach is 1.6 to 1.8. That's extremely acid. After the chime, (the partially digested food from the stomach), enters the duodenum, the pH is slowly raised to the six or seven range, as the pancreas delivers buffering compounds in the same area of the small intestine where the bile duct is located.

I think it's definitely worth a try. Colazal is another option, of course.

Good luck with whichever one you choose to try.

Tex

[ErinD]

Tex, you are such a wealth of knowledge Thank you!!

[tex]

You're very welcome.