OFFICE OF THE ATTORNEY GENERAL. STATE OF TEXAS
JOHN CORNYN
February 12,200l
The Honorable Toby Goodman Opinion No. JC-0341
Chair, Committee on Juvenile Justice
and Family Issues Re: Whether a Texas State Board of Pharmacy
Texas House of Representatives rule specifying that no drugs shall be included on
P.O. Box 2910 a list of narrow therapeutic index drugs is
Austin, Texas 78768-29 10 consistent with section 562.0 14 of the Texas
Occupations Code, which requires the Board, by
rule, to “establish a list of narrow therapeutic
index drugs” (RQ-0289-JC)
Dear Representative Goodman:
Section 562.014 of the Texas Occupations Code provides that the general statutory
provisions authorizing a pharmacist to substitute a generically equivalent drug for a prescribed drug
do not apply to the refill of a prescription for a “narrow therapeutic index drug” and charges the
Texas State Board of Pharmacy to “establish a list of narrow therapeutic index drugs.” TEX. OCC.
CODE ANN. 5 562.014 (Vernon 2001). You ask whether a Texas State Board of Pharmacy rule
specifying that no drugs shall be included on a list of narrow therapeutic index drugs, see 22 T.A.C.
8 309.3(d)(2) (2000) (Tex. State Bd. of Pharm., Prescription Drug Orders), is consistent with section
562.014.’ We conclude that the rule is consistent with section 562.014.
Title 3, subtitle J of the Texas Occupations Code, the Texas Pharmacy Act, TEX. Oct. CODE
ANN. chs. 55 l-566 (Vernon 2001), regulates the practice of pharmacy in this state. The Texas State
Board of Pharmacy (the “Board”) is charged with administering and enforcing the Act, see id. chs.
552,554, including regulating the delivery and distribution ofprescriptiondrugs, id. 8 554.005(a)(l),
and is authorized to adopt rules consistent with subtitle J, see id. 8 554.05 l(a).
Chapter 562, subchapter A, governs the authority of a pharmacist to dispense prescribed
drugs and to substitute generically equivalent products. Under subchapter A, a “generically
equivalent” drug means a drug that is pharmaceutically (i.e., chemically) and therapeutically
equivalent to the drug prescribed. See id. 5 562.001(l); see also id. § 562.001(2) (“‘Pharma-
‘See Letter from Honorable Toby Goodman, Chair, Committee on Juvenile Justice and Family Issues, to
Honorable John Comyn, Texas Attorney General (Sept. 25, 2000) (on file with Opinion Committee) [hereinafter
Request Letter].
The Honorable Toby Goodman - Page 2 (JC-0341)
ceutically equivalent’ means drug products that have identical amounts of the same active chemical
ingredients in the same dosage form and that meet the identical compendia1 or other applicable
standards of strength, quality, and purity according to the United States Pharmacopoeia or another
nationally recognized compendium.“); id. 0 562.001(3) (“‘Therapeutically equivalent’ means
pharmaceutically equivalent drug products that, if administered in the same amounts, will provide
the same therapeutic effect, identical in duration and intensity.“). If the physician’s signature on the
prescription form does not indicate that the prescription must be dispensed as written, the pharmacist
may select a generically equivalent drug. See id. 5 562.008. A pharmacist who selects a generically
equivalent drug must inform the patient of the substitution and of his or her right to refuse the
substitution or must display a sign providing notice regarding substitutions. See id. 5 562.009.
Subchapter A specifically provides that it is the legislature’s intent “to save consumers money by
allowing the substitution of lower-priced generically equivalent drug products for certain brand name
drug products.” Id. 8 562.002.
You ask about a rule adopted under section 562.014 of the Occupations Code, which limits
the authority of a pharmacist to refill a prescription using a generically equivalent drug as a
substitute for the drug originally prescribed, if that drug is a “narrow therapeutic index drug.”
Section 562.014 states as follows:
Except as provided by this section, drug selection as
authorized by this subchapter does not apply to the refill of a
prescription for a narrow therapeutic index drug. The board, in
consultation with the Texas State Board of Medical Examiners, shall
by rule establish a list of narrow therapeutic index drugs to which this
subsection applies. A prescription for a narrow therapeutic index
drug may be refilled only by using the same drug product by the same
manufacturer that the pharmacist last dispensed under the
prescription, unless otherwise agreed to by the prescribing physician.
If a pharmacist does not have the same drug product by the same
manufacturer in stock to refill the prescription, the pharmacist may
dispense a drug product that is generically equivalent if the
pharmacist, before dispensing the generically equivalent drug
product, notifies:
(1) the patient, at the time the prescription is dispensed, that
a substitution of the prescribed drug product has been made; and
(2) the prescribing physician of the drug product substitution
by telephone, facsimile, or mail, at the earliest reasonable time, but
not later than 72 hours after dispensing the prescription.
Id. 5 562.014.
The Honorable Toby Goodman - Page 3 (JC-0341)
The term “narrow therapeutic index drug” is not defined in the Texas Pharmacy Act or
elsewhere in the laws of this state. A Federal Food and Drug Administration regulation indicates
that a “narrow therapeutic index drug” is one that
exhibit[s] a narrow therapeutic ratio, e.g., there is less than a 2-fold
difference in median lethal dose . . . and median effective dose . . .
values, or [has] less than a 2-fold difference in the minimum toxic
concentrations and minimum effective concentrations in the blood,
and safe and effective use of the drug product[] requires careful
dosage titration and patient monitoring.
21 C.F.R. 8 320.33(c) (2000). A brief from the Texas State Board of Medical Examiners explains
that narrow therapeutic index drugs “are those medications where very small changes in the dosage
level could cause toxic results in patients.“2
Pursuant to section 562.014, the Board has adopted the following rule as a subpart to section
309.3 of title 22 of the Texas Administrative Code:
(d) Refills.
(1) Original substitution instructions. Refills shall follow the
original substitution instructions unless otherwise indicated by the
practitioner or practitioner’s agent.
(2) Narrow therapeutic index drugs.
(A) i’%eboard, in consultation with the Texas State Board
of Medical Examiners, has determined that no drugs shall be
included on a list of narrow therapeutic index drugs as defined in 9
562.013 [sic], Occupations Code. The board has specified in 8 309.7
of this title (relating to dispensing responsibilities) that pharmacist[s]
shall use as a basis for determining generic equivalency, Approved
Drug Products with Therapeutic Equivalence Evaluations and current
supplements published by the Federal Food and Drug Administration,
within the limitations stipulated in that publication.
(i) Pharmacists may only substitute products that are
rated therapeutically equivalent in the Approved Drug Products with
Therapeutic Equivalence Evaluations and current supplements.
*Brief from Ms. Michele L. Shackelford, General Counsel, Texas State Board of Medical Examiners, to
Ms. Susan D. Gusky, Chair, Opinion Committee l-2 (Nov. 16,200O) (on file with Opinion Committee).
The Honorable Toby Goodman - Page 4 (JC-0341)
(ii) Practitioners may prohibit substitution either by
signing on the “Dispense as Written” line of a written prescription
drug order or by clearly indicating on an oral prescription drug order
that the brand name product must be dispensed.
(B) The board shall reconsider the contents of the list if
the Federal Food and Drug Administration deter-r-nines a new
equivalence classification which indicates that certain drug products
are equivalent but special notification to the patient and practitioner
is required when substituting these products.
22 T.A.C. 8 309.3(d) (2000) (emphasis added); see also id. 9 309.7(b) (“Pharmacists shall utilize as
a basis for the determination of generic equivalency as defined in the Act, . . . Approved Drug
Products With Therapeutic Equivalence Evaluations and current supplements published by the
Federal Food and Drug Administration, within the limitations stipulated in that publication.“).
In short, the Board has determined that there are no “narrow therapeutic index drugs” for
which special rules should apply with respect to the use of generic substitutions in refills. As a
result, the same rules that apply to the use of generic substitutions in the filling of an original
prescription and refills generally apply to refills for narrow therapeutic index drugs. As with original
prescriptions and all other refills, see id. 66 309.3-.4, .7, pharmacists may substitute only products
that are rated therapeutically equivalent in the Federal Food and Drug Administration’s Approved
Drug Products with Therapeutic Equivalence Evaluations, see id. 8 309.3(d)(2)(i), and practitioners
may prohibit substitution either by signing on the “Dispense as Written” line of a written
prescription drug order or by clearly indicating on an oral prescription drug order that the brand
name product must be dispensed, see id. 5 309.3(d)(2)(ii).
You ask whether the Board “has met the legislative mandate of 6 562.014 of the Occupations
Code to adopt a list of NIT drugs by its determination that no list is a list.” Request Letter, supra
note 1, at 2. We conclude that the Board’s rule on narrow therapeutic index drugs satisfies the
legislature’s mandate and is therefore valid.
Your query suggests that the Board’s determination that there are no therapeutic index drugs
for which special refill rules should apply conflicts with section 562.014. In reviewing the rule, we
are guided by the maxim that “an agency can adopt only such rules as are authorized by and
consistent with its statutory authority.” Railroad Comm ‘n v. Arco Oil & Gas Co., 876 S.W.2d 473,
481 (Tex. App.-Austin 1994, writ denied). The critical factor in determining whether an
administrative agency has exceeded its rule-making authority is whether the rule’s provisions are
in harmony with the general objectives of the statute involved. Edgewood Indep. Sch. Dist. v. Meno,
917 S.W.2d 717,750 (Tex. 1995); Railroad Comm’n v. Lone Star Gas Co., 844 S.W.2d 679,685
(Tex. 1992). A court will uphold an agency rule if it is reasonable.
The Honorable Toby Goodman - Page 5 (JC-0341)
The Board’s rule is not in conflict with section 562.014. Again, section 562.014 provides
that, “[elxcept as provided by this section, drug selection as authorized by this subchapter does not
apply to the refill of a prescription for a narrow therapeutic index drug. The board, in consultation
with the Texas State Board of Medical Examiners, shall by rule establish a list of narrow therapeutic
index drugs to which this subsection applies.” TEX. Oct. CODEANN. 0 562.014 (Vernon 2001).
Section 562.014 imposes a mandatory duty on the Board to consult with the Board of Medical
Examiners and to enact a rule, see TEX. GOV’T CODEANN. 8 3 11.016(2) (Vernon 1998) (“‘Shall’
imposes a duty.“), which it has done. On its face, however, section 562.014 does not dictate the
substance of the rule or necessarily preclude the Board from determining that there are no narrow
therapeutic index drugs to which special refill rules should apply. Rather, the legislature has
delegated the authority to develop a list of narrow therapeutic index drugs to the Board, and specified
that it do so in consultation with the Board of Medical Examiners. In enacting this provision, the
legislature intended the Board, using its expertise and the expertise of the Board of Medical
Examiners, to exercise judgment and discretion in selecting drugs the refill of which should be
subject to special treatment. We do not believe it is inconsistent with this delegation of authority
for the Board to determine that there are no narrow therapeutic index drugs to which special refill
rules should apply.
Furthermore, we believe that the rule is in harmony with the general objectives of section
562.014. The purpose of section 562.014 appears to be to protect patients from adverse health
consequences from the substitution of generic drugs. It is clear from the face of the rule that the
Board has determined that use of the Federal Food and Drug Administration’s Approved Drug
Products with Therapeutic Equivalence Evaluations and physicians’ option to prohibit the use of
generic substitutions adequately protect patients. See 22 T.A.C. 8 309.3(d)(2)(i), (ii) (2000) (Tex.
State Bd. of Pharm., Prescription Drug Orders). In addition, we note that the purpose of subchapter
A is to encourage the use of generic drugs “to save consumers money.” TEX. OCC. CODEANN. 0
562.002 (Vernon 2001). The Board rule is in harmony with the general objectives of section
562.014 and the overall purpose of subchapter A.
As to whether the rule is reasonable, we defer, as we believe a court would, to the Board and
the State Board of Medical Examiners’ expertise in making judgments in this highly technical area.
See generally State v. Public Util. Comm ‘n of Tex., 883 S.W.2d 190, 197 (Tex. 1994) (“When an
administrative agency is created to centralize expertise in a certain regulatory area, it is to be given
a large degree of latitude in the methods it uses to accomplish its regulatory function.“).
In sum, the Board’s rule is consistent with section 562.014 and is in harmony with both the
general objectives of that statute and of subchapter A. We believe that a court would determine that
the rule is reasonable. We conclude that the rule is a valid exercise of the Board’s authority.
The Honorable Toby Goodman - Page 6 (JC-0341)
SUMMARY
A Texas State Board of Pharmacy rule, 22 T.A.C.
fj 309.3(d)(2) (2000) (T ex. State Bd. of Pharrn., Prescription Drug
Orders), which specifies that no drugs shall be included on a list of
narrow therapeutic index drugs to which special refill rules should
apply, is consistent with section 562.014 of the Texas Pharmacy Act,
TEX. Oct. CODEANN. 9 562.014 (Vernon 2001).
Attorney General of Texas
ANDY TAYLOR
First Assistant Attorney General
CLARK KENT ERVlN
Deputy Attorney General - General Counsel
SUSAN D. GUSKY
Chair, Opinion Comrnittee
Mary R. Crouter
Assistant Attorney General - Opinion Committee
Untitled Texas Attorney General Opinion
Combined Opinion