Paracetamol does not potentiate the acetylsalicylate inhibition of prostaglandin release from macrophages.

Prostaglandin (PGE2 and PGI2) synthesis can be stimulated in macrophages by the tumour promotor 12-O-tetradecanoylphorbol-13-acetate (TPA) and inhibited by acetylsalicyclic acid (IC50 = 8.2 x 10(-6) M) and paracetamol (IC50 = 1.9 x 10(-4) M). When mixture of both drugs were tested only an additive effect was observed. This result is in contrast to recent reports describing both potentiation of acetylsalicylate-induced PG synthesis inhibition and enhancement of PG production by paracetamol.