((a)) ** .—** Under regulations prescribed pursuant to , the Secretary of the military department concerned may, subject to subsection (c), pay retention special pay under this section to an officer who—

((1)) is a pharmacy officer in the Medical Service Corps of the Army or Navy or the Biomedical Sciences Corps of the Air Force; and

((2)) is on active duty under a call or order to active duty for a period of not less than one year.

((b)) ** .—** Subject to subsection (c), the Secretary of Health and Human Services may pay retention special pay under this section to an officer who—

((1)) is an officer in the Regular or Reserve Corps  of the Public Health Service and is designated as a pharmacy officer; and

((2)) is on active duty under a call or order to active duty for a period of not less than one year.

((c)) ** .—** Special pay may not be paid under this section to an officer serving in a pay grade above pay grade O–6.

((d)) ** .—** The amount of retention special pay paid to an officer under this section may not exceed $15,000 for any 12-month period.