I was browsing the (US) WebMD site and noticed that they have an entry for MT-2. It is interesting and surprisingly neutral in tone. It talks about use for tanning and for ED (no mention of Bremelanotide). But what is a bit weird about it is the dosage suggested: 0.025 mg/kg for both tanning and ED. By my calculation that means someone of moderate stature (180lbs) would be injecting just over 2mg a time, which seems to differ widely from general opinion.
WebMD gives their audience the ability to review medications and some of those are also interesting. For example one says....
"Have had further moles/freckles appear, this is not a problem. However I have developed oral melanotic macules from this makes my gums look black! (gingiva)Not a side effect that has been noted as far as my research has taken me. Oral melanotic macules ARE a side effect of medicines that change pigmentation of the skin"
I've not read of the black-gums side-effect anywhere else either.
The dosage information is outdated, and was scaled from testing on rats, I believe.
If you go back a couple of years people used that method but not so much any more as people realise it's over the top.
As the the darkened gums it is a side effect but it's rare.
It still needs UV to activate, and having your mouth closed is sufficient to prevent it. Imagine it'd take some doing to get your gums darkening though - and it's worth noting this happens naturally with tanning anyway.