Temgesic sublingual tablets come in only 0.2 mg and they're not scored. Buprenex ampoules are 0.3 mg/ml in 1-ml glass ampoule so that's about the maximum needed initially for acute pain.
Yes, 0.1 mg would be very safe for a person with little or no opiate tolerance and extremely severe pain. But for pain that severe, 10 on a 10 scale, it's probably not enough unless the person is extremely small or another reason for expecting hypersensitivity. Prior posts by mods saying 0.1 mg show strong bias towards maximizing safety which is the stated goal of this entire enterprise directed to harm reduction for recreational drug users. But a physician choosing an initial dose would be weighing safety on one side versus desirability of quickly relieving the person's suffering on the other. Actual product insert for Buprenex says: Pain medications work best if they are used as the first signs of pain occur. If you wait until the pain has worsened, the medication may not work as well. So, giving a cautious dose of 0.1 mg and waiting for maybe 2 hours before, what, taking another 0.1 or maybe 0.2 mg? Sounds like torture.
So that's the first comment, where I'd say the 0.2-mg strength of Temgesic in a tablet that can't be split is a good dose for moderate to severe acute pain because it's been widely considered safe for over 40 years used worldwide for acute pain but those tablets never caught on in the US. Maximum dose in an ER they'd be giving buprenorphine as Buprenex by IV or IM and the 0.3-mg dose of one ampoule is so standard they now have disposable auto-injectors pre-loaded with the 0.3 mg dose and everyone over the age of 13 gets the same dose: (buprenorphine) is indicated for the relief of moderate to severe pain. DOSAGE AND ADMINISTRATION. Adults: The usual dosage for persons 13 years of age and over is 1 ml Buprenex (buprenorphine) (0.3 mg buprenorphine).
There was a thread a month ago on making a liquid from Suboxone films and people there and now are using that liquid as if it's Buprenex and squirting volumetric doses in the mouth and talking about the dose from buprenorphine used either for pain or opiate maintenance. But Suboxone is not Subutex, and the naloxone makes a big difference in that drug's effect. I've had about nine years of Suboxone treatment first with name-brand tablets, then films, then the two generics and if you make a water or water/alcohol solution from them it's not the same drug as Buprenex. So call it liquid Suboxone or Suboxone in water because it's not buprenorphine and it's not equivalent to Buprenex. I've had name-brand Temgesic and a long time ago when it was a C-5 before Suboxone came along we'd get it from Mexican farmacias on the border and they'd get almost $2 per 0.2-mg tab because people loved them and it was a very nice high.
So, mg for mg, people did and still continue to pay much more for plain buprenorphine than they'd pay for the naloxone mixture. Some people might not mind the naloxone or maybe that's all they've ever known. But Temgesic and Buprenex are still sold, and there are new formulations like the Sublocade for subcutaneous long-acting opiate maintenance and Simbadol which is a 24-hr buprenorphine injection for cats only, for vets to use for post-operative pain so they don't send the cat home with pre-measured doses Buprenex. Buprenorphine is becoming very popular!
When I wanted to make a buprenorphine solution I went to a methadone clinic doctor and got a scrip for Subutex, and the generic 8-mg made by HI-TECH are the tiniest little white tablets that dissolve in water very quickly. If you can't get Buprenex that's how you could have a home-made water solution of plain buprenorphine.
Then there's the issue of loss of drug from incomplete dissolution of film into the solvent liquid. The films in water become a gel and you'd have no way of knowing how much drug is retained in your glassware and any filter. One way to minimize those losses is to dedicate the equipment to only that drug so you're not washing it down the drain, at least it's not being thrown away and after a while it'll reach an equilibrium load from the film being deposited on the surfaces exposed to the liquid. The film is designed so that the active drugs migrate out of the film and adhere to tissue in the person''s mouth. Out of the film and onto a surface. Well, if you dissolve the film in liquid in a small beaker you'll have drug adhering to the glass. How much drug adheres to the surfaces? I'd guess that if you're starting with clean glass it could be approximately half of the drug adhering to the glass.
I use dedicated equipment with my poppy pod preparation equipment, never cleaning it and using it only with poppy, which meant reserving a $4 coffee grinder for use with pods only and not using it for coffee. And there's a 150-ml flask used only for making a diazepam/olive-oil solution and the undissolved diazepam stays in the flask and eventually i'll clean it if the crud turns a darker brown but I'll be using cotton to trap the sludge and not throw it away.