Disclosed aspects relate to methods and apparatus for coexistent radio frequency (RF) systems in a wireless device. Control of a wireless device includes detecting when a turn on signal is issued to a first radio system, and then controlling the second radio system to either modify the operation of receiver circuitry in the second radio system to protect components within that system, or modify transmit circuitry to stop transmissions for protecting components within one radio system potentially affected by transmission from the other radio system in the wireless device. Disclosed also is monitoring of transmission states of the radio systems based on reading messages between the first and second radio systems and issuing a notification message based thereon such that one of the radio systems may suspend monitoring of a transmit channel for permission to transmit in order to reduce power consumption due to such monitoring of the channel.