West syndrome (WS) is a severe age-dependent intractable epilepsy in infants that frequently results in mental retardation. ACTH or glucocorticoids are among several effective treatments in WS, but the relative advantages and disadvantages of these two therapies are still unknown. In a previous study, liposteroid (LS; dexamethasone palmitate) was used for the treatment of WS and compared with ACTH therapy in relation to therapeutic effect and adverse reactions. In this study, a new regimen of LS therapy was tried for WS and its related syndrome in an attempt to hasten the onset of the therapeutic effect and reduce the relapse rate. A single intravenous injection of LS (0.25 mg/kg) was administered 12 times in 1 month (total dosage 3.0 mg/kg) to four patients with WS and with post-WS aged 5–25 months, and one patient with Lennox–Gastaut syndrome (post-WS) aged 84 months. All five patients had daily seizures uncontrolled by conventional antiepileptic drugs, such as VPA, CZP or ZNS. Nodding spasm and hypsarrhythmia on EEG disappeared in one patient with WS within four doses. More than 50% decrease in seizures, and EEG improvement, were found in other two patients. No notable effects were seen in the other two patients. There were no clinically significant adverse reactions throughout the therapy. Efficacy can be determined in this new experimental LS therapy earlier than with conventional LS therapy. In this small study, a new protocol for LS therapy could be completed safely. This regimen may be useful for those susceptible to adverse reactions from conventional treatment or those unresponsive to other treatments.