Pipamperone (INN, USAN, BAN), also known as Carpiperone and Floropipamide or Fluoropipamide, and as Floropipamide hydrochloride (JAN), is a typical antipsychotic of the butyrophenone family used in the treatment of schizophrenia. It is or has been marketed under brand names including Dipiperon, Dipiperal, Piperonil, Piperonyl, and Propitan. Pipamperone acts as an antagonist of the 5-HT2A, 5-HT2B, 5-HT2C D2, D3, D4, α1-adrenergic, and α2-adrenergic receptors. It shows the much higher affinity for the 5-HT2A and D4 receptors over the D2receptor (15-fold in the case of the D4 receptor, and even higher in the case of the 5-HT2A receptor), is regarded as "highly selective" for the former two sites at low doses. Pipamperone has low and likely insignificant affinity for the H1 and mACh receptors, as well as for other serotonin and dopamine receptors. Low-dose pipamperone (5 mg twice daily) has been found to accelerate and enhance the antidepressant effect of citalopram. Pipamperone is approved in some European countries. At its usually recommended antipsychotic dose (120–360 mg/d), it has relatively weak neuroleptic activity because it is only moderately effective as a dopamine D2-receptor antagonist, even at high doses.