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August 29[edit]

Drugs with low oral bioavailability[edit]

For a university project, I'm trying to identify drugs that suffer from low oral bioavailability. Does anyone know of specific examples? Or of any resources where I could search for such information? Thank you. — Preceding unsigned comment added by TEA student (talk • contribs) 16:58, 29 August 2016 (UTC)[reply]

To TEA student: I believe that almost all peptides and proteins are digested so they have abysmal oral availability (e.g.: insulin, growth hormone, noopept, semax, selank) and steroids (e.g. testosterone, estradiol) taken orally are partially degraded because of to the first pass effect. Steroids can still be administered orally, but I believe that the doses required are higher than when using a parenteral ROA. Mario Castelán Castro (talk) 17:19, 29 August 2016 (UTC).[reply]

There is a huge number of such drugs. Could you be more specific? For what condition do you need such drugs? Ruslik_Zero 17:38, 29 August 2016 (UTC)[reply]

I think his "condition" is scholasticus discipula. 2606:A000:4C0C:E200:4BF:6AED:D301:8167 (talk) 18:34, 29 August 2016 (UTC)[reply]

I'm not looking at any specific medical condition. Sorry if I wasn't clear. This is for a research/writing assignment in an educational environment. TEA student (talk) 18:44, 29 August 2016 (UTC)[reply]

To User:Mario Castelán Castro. Thank you for the suggestions. I'll look into the bioavailability issues associated with steroid-based pharmaceuticals. TEA student (talk) 18:44, 29 August 2016 (UTC)[reply]

Insulin or any analog and Victoza or its variations which is a Gila monster-venom analog. There are also antivomitting drugs or drugs given to patients who vomit which are administered sublingually, such as hyoscyamine. BTW, if your doctor prescribes sublingual hyoscyamine, ask him if he's ever eaten an ounce of morning glory seeds. μηδείς (talk) 20:32, 29 August 2016 (UTC)[reply]

What do “5-IT” and “6-IT” stand for (as names of psychoactive substances)?[edit]

Hello. The drugs 5-(2-aminopropyl)indole and 6-(2-aminopropyl)indole are also known as “5-IT” and “6-IT” respectively. What do these short names mean?. They give the appearance of being an abbreviation but I can't figure what they stand for. By contrast, “5-API” and “6-API” are obvious abbreviations of “5/6-(2-aminopropyl)indole”. Regards. Mario Castelán Castro (talk) 17:07, 29 August 2016 (UTC).[reply]

My guess (based on the article) is that I is isopropylamine and the T is tryptamine, even though it's not actually a tryptamine. shoy (reactions) 17:16, 29 August 2016 (UTC)[reply]

To Shoy: thanks for answering. Yes, it is possible. The problem is that as you said, that these drugs are not substituted tryptamines nor do they even have a tryptamine core anywhere. Maybe whoever had chosen that name did incorrectly thought that indole is called “tryptamine” or something similar. Does anybody has a more fitting explanation or a source for this one?. Mario Castelán Castro (talk) 17:25, 29 August 2016 (UTC).[reply]

Most if not all of these cute little abbreviations trace back to PIHKAL/TIHKAL. I think Alexander Shulgin came up with them himself, and I don't think it's an actual chemical standard. The 6-IT article gives the sense that he was thinking of these as the "5-isomer" and "6-isomer" of tryptamine, perhaps? Wnt (talk) 18:24, 29 August 2016 (UTC)[reply]

To Wnt: I had not thought that Alexander Shulgin simply invented those names. Thanks for the reference to Shulgin's Books. The question still remains of whether there is a verifiable origin for the names “5-IT” and “6-IT”. Any idea?. Mario Castelán Castro (talk) 22:02, 29 August 2016 (UTC).[reply]

Well, I think he explains that they're just provisional nicknames somewhere in there ... but it's been a long time since I looked at them. Wnt (talk) 11:48, 30 August 2016 (UTC)[reply]

Glaciated landscapes[edit]

Why do the landscapes of the Yorkshire Dales and the Lake District differ when they're both glaciated limestone landscapes? 2A02:C7D:B903:6C00:302D:3D32:70D6:6F72 (talk) 19:58, 29 August 2016 (UTC)[reply]

@Mikenorton: is a structural geologist based in the UK. μηδείς (talk) 20:27, 29 August 2016 (UTC)[reply]

Links: Yorkshire Dales, Lake District; & Karst topography might be relevant. 2606:A000:4C0C:E200:4BF:6AED:D301:8167 (talk) 20:41, 29 August 2016 (UTC)[reply]

Much of the lake district is not limestone, see Lake district#Geology and [1] and, indeed, there is other geology than just limestone in parts of the Dales.The geology of the two landscapes is entirely different. Richerman (talk) 21:09, 29 August 2016 (UTC)[reply]

There is very little limestone in the Yorkshire Dale where I live. Dbfirs 10:55, 30 August 2016 (UTC)[reply]

They aren't really both "glaciated limestone" - although this does depend a lot on where you draw the boundary for "the Lakes". If you look at Western Lakeland, you see far more prominent glacial features and you see millstones rather than limestone, so no Karst pavements. There's a large area of the Pennines in between the two which is classical limestone country - I'd even suggest that "the Dales" are mostly to the East of this and so nothing like as classically limestone in nature.

As always for UK geology, the little green British Geological Survey / HMSO 'British Regional Geology' booklets are well-priced and a good introduction. Andy Dingley (talk) 17:22, 30 August 2016 (UTC)[reply]

The geology of the Lake District is dominated by the Ordovician Skiddaw Group shales and Borrowdale Volcanic Group, with most of the major fells in the latter. Limestone are restricted to part of the Windermere Supergroup in the southeastern lakes. The Yorkshire Dales are mainly Carboniferous, Carboniferous Limestone and particularly Millstone Grit. So the geology is different, as has been pointed out above, but also the glaciation is different. Most of the dales will have been affected by the large ice sheets moving southwards, whereas the Lake District massif had its own icecap, which gouged out the deep valleys and left the classic glaciated topography. Mikenorton (talk) 22:22, 30 August 2016 (UTC)[reply]