Insert the tip of the drench gun into the corner of the mouth and get it on top of the tongue, at least as far as the back teeth before you depress the plunger
Radrizzani D, Bertolini G, Facchini R, Simini B, Bruzzone P, Zanforlin G, et al
A true labial melanotic macule is benign and does not transform into melanoma
Some of these adverse effects reported were Toxic Epidermal Necrolysis (a rare but life-threatening skin condition characterized by painful blisters and large areas of skin peeling), air embolism, thyroid dysfunction, and liver, kidney, and neurologic toxicity (The dark side of skin lightening- PubMed) With the proliferation of med-spas in an unregulated fashion, there is a risk of inadequately trained or untrained people giving IV injections in a non-sterile way, which can lead to sepsis and transmission of infections like HIV and hepatitis