In body area network (BAN) systems, many BANs in close proximity may lead to unacceptable interference. Multiuser detection (MUD) has drawn a great deal of interest for interference rejection issue in conventional wireless CDMA systems. MUD receivers overcome the impairments of the matched filter by considering the multiple access interference (MAI) as a useful information in the detection process. This allows them to mitigate the self-interference and the near far problems, inherent in the matched filter, which results in capacity enhancement. In this paper, in addition to the matched filter, we study the performance of the decorrelator and the minimum mean square error (MMSE) receivers in the BANS which are presented as a strong candidate in the emerging 4G wireless systems. It is shown that these receivers perform similarly in the presence of synchronous users, whatever the number of users is. On the other hand, in an asynchronous scenario, the matched filter's performance degrades drastically unlike the two other detectors which are shown to be more robust.