Assuming that you mean mucus from the nostrils, doctors normally prescribe anti-histamines. Apparently production of mucus in the nostrils is attributed to allergens that provoke histamine to produce mucus from mast cells.
Ambroxol and bromhexine are two drugs that liquefy the mucus.
an expectorant
Sandstone is the rock that results when sand liquefies.
They are relatively safe, but not drug free. And your mucus membranes can get dependant on it.
expectorant
It meltes and then turns Into liquid
The stomach
It can shake it about so that it liquefies.
Black mucus is usually dried blood. Snorting coke will definitely do it, and just about any upper (all of which dry out the mucus membranes) will do it in dry weather, depending on the condition of the user's capillary bed.
The melting point which is at 100 Celsius.
latent heat
It can be sniffed if purchased in powder or it can be put in a drink) you can also inject it & it can be absorbed through mucus membrane.
Benadryl (diphenhydramine) is considered an anti-histamine drug which means it is supposed to decrease the amount of fluid congested in the mucus membrane tissues. So, in general, it should dry out the tissues and not thicken the mucus.
stomach