It looks like it's a state law what you can and can't change on a C2.
CHANGES TO SCHEDULE II PRESCRIPTIONS
Recently adopted rules for multiple Schedule II prescriptions by the Drug Enforcement Administration (DEA) appear to conflict with a long standing DEA policy regarding what a pharmacist may change on a Schedule II prescription after consultation with the prescribing practitioner. Because of this confusion, DEA issued a letter on October 15, 2008, that contains the following statement:
"DEA recognizes the Resultant Confusion regarding this conflict and plans to resolve this matter through a future rule making. Until that time, pharmacists are instructed to adhere to state regulations or policy regarding those changes that a pharmacist may make to a schedule II prescription after oral consultation with the prescriber."
Representatives of the Texas State Board of Pharmacy (TSBP) met with representatives of the Texas Department of Public Safety (DPS) on October 31, 2008, and have agreed that the following four (4) items on a Schedule II prescription
MAY NOT BE CHANGED.
Name of the patient
Name of the drug
Name of the prescribing physician
Date of the prescription
Any other item, such as the strength of the drug, quantity of the drug, and directions for use,
MAY BE CHANGED PROVIDED, the pharmacist:
(1) contacts the prescribing physician and obtains verbal permission for the change; and
(2) documents on the prescription the following information:
(a) change that was authorized;
(b) name or initials of the individual granting the authorization; and
(c) initials of the pharmacist.