Compound 48/80 trihydrochloride (C48/80 trihydrochloride) is a mixture of N-methyl-p-methoxyphenethylamine and formaldehyde in a condensation reaction.Compound 48/80 trihydrochloride is a mast cell degranulator and histamine releaser. Compound 48/80 trihydrochloride inhibits phosphatidylinositol-specific phospholipase C activity in human platelets.

Compound 48/80, also known as Poly-p-methoxyphenethylmethylamine, is a commonly utilized mast cell activator in animal and tissue models. This compound exerts its effect by stimulating trimeric G-proteins at the mast cell membrane, triggering degranulation through both phospholipase C and D pathways.