A method and an apparatus for alleviating congestion of a wireless medium used by an access point (AP) and a plurality of wireless transmit/receive units (WTRUs) are disclosed. If congestion is determined to exist on the wireless medium, a determination is then made as to whether there are any low priority traffic streams established between the AP and at least one of the WTRUs. If there are no low priority traffic streams established between the AP and at least one of the WTRUs, selected ones of the associated WTRUs are disassociated with the AP based on the amount of time spent by the WTRUs trying to transmit and retransmit unacknowledged packets or on a specific traffic stream access category. If low priority traffic streams have been established, the packet transmission delay associated with the low priority traffic streams is increased when congestion exists. Otherwise, the packet transmission delay is decreased.