This chapter does not apply to amounts derived as compensation for services rendered to patients or from sales of drugs for human use pursuant to a prescription furnished as an integral part of services rendered to patients by a kidney dialysis facility operated as a nonprofit corporation, a nonprofit hospice agency licensed under chapter
70.127 RCW, and nursing homes and homes for unwed mothers operated as religious or charitable organizations, but only if no part of the net earnings received by such an institution inures directly or indirectly, to any person other than the institution entitled to deduction hereunder. "Prescription" and "drug" have the same meaning as in RCW
82.08.0281.