Many times, the rep needs a DEA number to write in to their book as an identifying number as to who received the samples.
Many PAs do receive samples.
It should be a delegated authority to the PA from the sueprvising physician. The IAPA advocates you write it down as a responsibility and both the supervising doc and PA sign it. You must wait to have the DEA number in hand before wiritng for controlled substances. For uncontrolled substances, simply have the supervising doc sing off, mail it in and start prescribing. You do not have to have the letter of acknowledgement from the IDPR to write for uncontrolled substances.