Was it legal for Maryland veterinarians to euthanize dogs and cats with T-61 solution, or did that count as a banned 'curariform drug'?

Plain-English summary

A member of the Maryland House of Delegates asked the Attorney General to resolve a dispute over whether veterinarians and animal control officers could legally use "T-61 Euthanasia Solution" to euthanize dogs and cats, given that Article 27, §59A made it a misdemeanor to kill a dog or cat using "curariform drugs," and some scientific literature described one of T-61's three components as having a curare-like effect. The State Board of Veterinary Medical Examiners had informally concluded the statute did not cover T-61, and the delegate asked the Attorney General to settle the question. The opinion concluded T-61 is not a prohibited "curariform drug" because, even though one of its ingredients blocks nerve-to-muscle signals like curare, T-61's general anesthetic component induces unconsciousness first, before the curariform component causes respiratory paralysis, so the animal does not experience the suffocation and intense anxiety that made pure curariform drugs (like succinylcholine, which acts on a conscious animal) the specific target of the statute's ban.

Currency note

This opinion was issued in 1982. Subsequent statutory amendments, court decisions, or later AG opinions may have changed the analysis. Treat this page as historical context, not current legal advice. Verify current law before relying on any specific rule, deadline, or remedy mentioned here.

The opinion's conclusion rested on the scientific and veterinary literature about T-61 and curariform drugs available as of 1982, on the specific text of Article 27, §59A as it then existed, and on federal drug approvals in place at the time. Veterinary euthanasia standards, the statute's codification, and federal drug regulation have all had decades to change since 1982, and this or similar euthanasia products may since have been reformulated, relabeled, discontinued, or reclassified. Anyone researching which euthanasia methods are currently permitted for animals in Maryland should verify the current statute and current veterinary guidance rather than relying on this opinion's 1982 analysis.

Common questions

Did Maryland law in 1982 ban all drugs that act like curare when used to euthanize a dog or cat?
Yes, Article 27, §59A banned killing a dog or cat with "curariform drugs," among other prohibited methods. The dispute in this opinion was whether T-61, a combination product containing one component with a curare-like effect, fell within that ban.

Why did the opinion conclude T-61 wasn't covered, even though it contains a curare-like ingredient?
The opinion found that "curariform drugs," as a technical term used by veterinarians, specifically meant drugs that paralyze an animal's breathing muscles without first depressing its consciousness, so the animal suffocates while still aware. T-61's general anesthetic component takes effect first and induces unconsciousness before its curare-like component causes respiratory paralysis, so the scientific literature indicated the animal does not experience the suffocation and anxiety the statute was aimed at preventing.

Did the sponsors of the 1979 law say what they were trying to accomplish?
The opinion pointed to the title of the enacting legislation, Chapter 342, Laws of Maryland 1979, which described the act as relating to "the humane killing of dogs and cats," and reasoned that the General Assembly meant to ban only methods it considered inhumane, not every drug that happens to share one pharmacological property with a banned drug.

Was T-61 approved by any other authority as a humane euthanasia method?
Yes. The opinion noted that T-61 was one of only two drugs specifically approved by the Bureau of Veterinary Medicine of the U.S. Food and Drug Administration at the time as effective for "the humane euthanasia of animals without excitation or pain," and that it met most of the American Veterinary Medical Association's own criteria for evaluating euthanasia methods.

Background and statutory framework

Article 27, §59A, enacted in 1979, made it a misdemeanor to kill a dog or cat using a decompression chamber, carbon monoxide gas, or curariform drugs, but did not define "curariform drugs." The opinion applied Maryland's rules for construing technical terms in statutes, concluding that where the scientific and veterinary community uses a term with a specific, technical meaning, that meaning controls over a looser dictionary definition unless the legislature clearly intended otherwise. Drawing on veterinary literature, including the American Veterinary Medical Association's 1978 Panel on Euthanasia report and a veterinary pharmacology text, the opinion found that veterinarians use "curariform drugs" to mean agents like succinylcholine and gallamine that paralyze respiratory muscles without depressing consciousness, so the animal remains aware while suffocating, a result veterinary authorities considered inhumane and specifically warned against.

The opinion then examined T-61's pharmacology in detail. T-61 combines a general anesthetic that rapidly induces deep unconsciousness and eventual cerebral death, a neuromuscular blocking agent with a curare-like effect that relaxes skeletal muscles and contributes to respiratory paralysis, and a local anesthetic that eases the injection itself. Citing the manufacturer's package insert and comparative veterinary studies (including one comparing T-61 to pentobarbital, an accepted barbiturate euthanasia agent), the opinion found that T-61's anesthetic component depresses the central nervous system and produces unconsciousness before its curariform component takes effect, so unlike a pure curariform drug, T-61 does not leave the animal conscious while its breathing muscles fail. The opinion also looked to the legislative title of Chapter 342, Laws of Maryland 1979, which framed the statute's purpose around "humane killing," and reasoned that reading §59A to ban T-61 despite its functional similarity to already-permitted central-nervous-system depressants would produce an illogical result under Maryland's rules of statutory construction, particularly since T-61 met most of the AVMA's own criteria for humane euthanasia and was one of only two agents the FDA's Bureau of Veterinary Medicine had specifically approved as effective for humane, pain-free animal euthanasia. Because it resolved the question on this statutory-construction ground, the opinion expressly declined to address whether banning T-61 might also have raised separate federal preemption or Commerce Clause problems.

Citations

Statutes:

• Article 27, §59A of the Maryland Code
• Chapter 342, Laws of Maryland 1979
• Article 27, §276 et seq. of the Maryland Code
• Art. 27, §279(b)d.4
• 21 U.S.C. §801 et seq.
• 21 C.F.R. §522.900
• 46 Fed. Reg. 23,232 (April 24, 1981)
• 41 Fed. Reg. 45,547 (Oct. 15, 1976)
• U.S. Const. art. VI, cl. 2
• U.S. Const. art. I, §8, cl. 3

Cases:

• Mauzy v. Hornbeck, 285 Md. 84, 92 (1979)
• State v. Fabritz, 276 Md. 416, 421 (1975), cert. denied, 425 U.S. 942 (1976)
• Maguire v. State, 192 Md. 615, 623, 65 A.2d 299, 302 (1949)
• Health Servs. Cost Review Comm'n v. Holy Cross Hosp. of Silver Spring, Inc., 290 Md. 508, 516 (1981)
• Reed v. State, 283 Md. 374, 438 (1978) (Smith, J., dissenting)
• State Farm Mut. Auto. Ins. Co. v. Insurance Comm'r, 283 Md. 663, 674 n.3 (1978)
• Commission on Human Relations v. Mayor & City Council of Baltimore, 280 Md. 35, 41 (1977)
• State v. Wagner, 15 Md. App. 413, 422 (1972)
• State v. Berry, 287 Md. 491, 496 (1980)
• Kindley v. Governor, 289 Md. 620, 625 (1981)
• Comptroller v. John C. Louis Co., Inc., 285 Md. 527, 539 (1979)
• Cider Barrel Mobile Home Court v. Eader, 287 Md. 571, 583 (1980)
• Pharmaceutical Soc'y of the State of N.Y., Inc. v. Lefkowitz, 454 F. Supp. 1175, 1178-80 (S.D.N.Y.), aff'd, 586 F.2d 953 (2d Cir. 1978)
• Cosmetic, Toiletry & Fragrance Ass'n, Inc. v. Minnesota, 440 F. Supp. 1216, 1220-25 (D. Minn. 1977), aff'd per curiam, 575 F.2d 1256 (8th Cir. 1978)

Source

• Landing page: https://oag.maryland.gov/resources-info/Pages/attorney-general%E2%80%99s-opinions.aspx
• Original PDF: https://oag.maryland.gov/resources-info/Documents/pdfs/Opinions/1982/Volume67_1982.pdf

Original opinion text

Best-effort transcription from a scanned PDF. Minor errors may remain, the linked PDF is authoritative.

CRIMINAL LAW

Cruelty to Animals—Euthanasia of Dogs and Cats—"T-61 Euthanasia Solution" Not a Prohibited "Curariform Drug"

May 6, 1982

The Honorable Idamae Garrott
Maryland House of Delegates

You have requested our opinion about the use of a proprietary euthanasia agent known as T-61 Euthanasia Solution ("T-61") by veterinarians and animal control officers in Maryland.1 Specifically, you ask whether the use of this agent violates Article 27, §59A of the Maryland Code, which prohibits the killing of a dog or cat by use of "curariform drugs".2 You have advised us that the State Board of Veterinary Medical Examiners has informally concluded that §59A does not proscribe the use of T-61, even though certain scientific literature indicates that this euthanasia agent contains a "curariform" component. To help resolve this controversy, you have requested our advice.

For the reasons discussed below, we believe that T-61 is not a "curariform drug" within the meaning of §59A and that its use is consonant with the underlying policy of that statute, the humane killing of dogs and cats.

1 "T-61" is the registered trademark of the American Hoechst Corporation, Somerville, New Jersey 08876, which distributes this drug under the trade name "T-61 Euthanasia Solution".

2 Article 27, §59A, enacted in 1979, provides:

"(a) A person may not kill or permit to be killed a dog or cat by the following means:

(1) Use of the high-altitude, low-pressure chamber (commonly known as decompression chamber);

(2) Use of carbon monoxide gas;

(3) Curariform drugs.

(b) A person violating this section is guilty of a misdemeanor and subject to a fine of not more than $500."

I
Definition of "Curariform Drug"

To determine whether T-61 is a "curariform drug" within the meaning of §59A and, therefore, whether its use as a euthanasia agent for dogs and cats is prohibited in Maryland, the term "curariform drugs" must be defined.

The cardinal rule in the construction of statutes is to effectuate the real and actual intention of the General Assembly, and statutes are to be construed reasonably with reference to the purpose to be accomplished. E.g., Mauzy v. Hornbeck, 285 Md. 84, 92 (1979); State v. Fabritz, 276 Md. 416, 421 (1975), cert. denied, 425 U.S. 942 (1976). As the Maryland Court of Appeals observed in State v. Fabritz:

"[A]s stated in Maguire v. State, 192 Md. 615, 623, 65 A.2d 299, 302 (1949), '[a]dherence to the meaning of words does not require or permit isolation of words from their context "*** [since] the meaning of the plainest words in a statute may be controlled by the context. . . In construing statutes, therefore, results that are unreasonable, illogical or inconsistent with common sense should be avoided whenever possible consistent with the statutory language, with the real legislative intention prevailing over the intention indicated by the literal meaning.

... In the final analysis, in construing any statute requiring construction, courts must consider not only the literal or usual meaning of words, but their meaning and effect in light of the setting, the objectives and purposes of the enactment, with the real intention prevailing over the literal intention even though such a construction may seem to be contrary to the letter of the statute." 276 Md. at 422 (emphasis added) (citations omitted).

A corollary rule of construction to be considered here involves the use of technical terms or "terms of art" in a statute. In the absence of a legislative intent to the contrary, a technical term or term of art in a statute is presumed to have been used with its technical meaning. 2A Sutherland, Statutory Construction §47.29 (C. Sands 4th ed. 1973). Recently, the Court of Appeals defined "words of art" to mean:

"The vocabulary or terminology of a particular art or science, and especially those expressions which are idiomatic or peculiar to it." Health Servs. Cost Review Comm'n v. Holy Cross Hosp. of Silver Spring, Inc., 290 Md. 508, 516 (1981) (quoting Black's Law Dictionary 1439 (rev. 5th ed. 1979)).

In Holy Cross, the Court of Appeals observed that until an alleged trade or commercial meaning of a term is proven, it is presumed to be the same as the common meaning. Id. See also 2A Sutherland, Statutory Construction, supra, §47.31. For a technical meaning of a term to prevail,

"'it must appear that such commercial meaning is the result of established usage in commerce or trade, and that, at the time of the passage of the act, such usage was definite, uniform, and general, and not partial, local, or personal.'" HSCRC v. Holy Cross, 290 Md. at 516 (quoting 2A Sutherland, Statutory Construction, supra, §47.31, at 156).

Applying these principles to §59A, it must be determined whether the phrase "curariform drugs" is a term of art and, if so, whether its technical meaning should prevail over its common meaning. Because the statute does not define "curariform drugs", we must consider other sources to ascertain its intended meaning.

The root of the word "curariform" is "curare", which is defined in Webster's New World Dictionary 346 (2d college ed. D. Guralnik 1978) as

"a black, resinous substance prepared from the juices of certain S. American plants and used by some Indians for poisoning arrows: it causes motor paralysis when introduced into the bloodstream and is used in medicine to relax muscles, as during surgery." (Emphasis added.)

Stedman's Medical Dictionary 343 (23d ed. 1976) adds:

"Used intravenously or intramuscularly, it produces muscular paralysis by preventing motor nerve impulses from causing normal contraction of skeletal muscles. Death results from paralysis of the respiratory muscles." (Emphasis added.)

See also Dorland's Illustrated Medical Dictionary 389 (25th ed. 1974). The adjective ["curariform"] is unhelpfully defined as "[d]enoting a drug having an action like curare". Stedman's Medical Dictionary, supra, at 343. See also Dorland's Illustrated Medical Dictionary, supra, at 389.

Thus, "curariform drugs" denotes drugs that produce muscular paralysis by preventing motor nerve impulses from causing the normal contraction of skeletal muscles. If such a drug is administered in sufficiently large quantities, death results from a lack of oxygen due to paralysis of the respiratory muscles (i.e., hypoxia).

Based on the scientific literature available prior to the enactment of §59A in 1979, the term "curariform drugs" apparently had a more specific and technical meaning than that suggested by the preceding dictionary definitions. The latest report of the American Veterinary Medical Association Panel on Euthanasia ("AVMA Panel"), issued in 1978, defines "curariform drugs" as follows:

"Curariform Drugs—Drugs such as curare, succinylcholine, pancuronium, glyceryl fenesin, and other neuromuscular blocking agents produce death by immobilizing the respiratory muscles, causing fatal suffocation. There is no depressant action on the brain. . . . Human patients given these drugs have described periods of full consciousness accompanied by complete muscular immobility and intense anxiety." American Veterinary Medical Association, Report of the AVMA Panel on Euthanasia, 173 J. Am. Vet. Med. Ass'n 59, 69 (1978) (emphasis added) (footnote omitted) [cited below as "AVMA Report"].3

Another veterinary medical authority, written in 1977, offers a similar definition:

"Drugs such as d-tubocurarine, gallamine, decamethonium, and succinylcholine cause rapid collapse due to neuromuscular paralysis. Consciousness is not affected. Death is due to anoxemic anoxia, which results from inability of the respiratory muscles to function. These agents should not be used to kill animals." Hatch, "Euthanatizing Agents", Veterinary Pharmacology and Therapeutics 1289, 1294 (4th ed. L. Jones, N. Booth & L. McDonald eds. 1977) (emphasis added).

3 Regarding the curare-like effects of succinylcholine, see Reed v. State, 283 Md. 374, 438 (1978) (Smith, J., dissenting).

These definitions of "curariform drugs" reveal that the term, as used both prior to and since the enactment of §59A, is a "term of art". That is, for the relevant scientific community, the "definite, uniform, and general" usage of the term connotes a drug having a curare-like effect that does not affect consciousness. Because §59A is most likely to be enforced against veterinarians and animal control officers, it is reasonable to assume that the General Assembly intended the language of this penal statute to inform that group of persons about which euthanasia methods are prohibited. Hence, veterinarians' understanding and interpretation of this term of art ought to be accorded significant weight.

In summary, the scientific literature reveals that when veterinarians refer to "curariform drugs" they mean euthanasia agents that do not immediately affect consciousness prior to death due to respiratory paralysis and, ultimately, lack of oxygen. The unsuitability of pure curariform drugs (e.g., succinylcholine, gallamine) lies in the fact that the animal is conscious while it literally suffocates to death. Although the common usage of the term "curariform drugs" might not reflect this crucial distinction, we nevertheless are persuaded, for the reasons set forth below, that the General Assembly intended to adopt the technical and narrower meaning of "curariform drugs" in the context of §59A.

II
Attributes and Effects of T-61

T-61 is a combination drug consisting of three chemically and pharmacologically different components. Each milliliter contains the following active ingredients: (1) 200 milligrams ("mg") of N-[2-(m-methoxy-phenyl)-2-ethyl-butyl-(l)]-gama-hydroxybutyramide, a general anesthetic that induces rapid and deep anesthesia, followed by respiratory arrest, cerebral death, and circulatory collapse; (2) 50 mg of 4, 4'-methylene-bis (cyclohexyl-trimethyl-ammonium iodide), a neuromuscular blocking agent that induces skeletal muscular relaxation by blocking the transfer of stimuli from nerve endings to muscle fibers; and (3) 5 mg of tetracaine hydrochloride, a local anesthetic that permits completion of the injection without local pain or struggling. See Package Insert for T-61 Euthanasia Solution, American Hoechst Corporation, Animal Health Division (1980).4

4 Each milliliter of T-61 also contains 0.6 milliliters of dimethylformamide in distilled water.

The manufacturer describes T-61's pharmacodynamic effect as follows:

"The sequence of neurological effects of T-61®, when properly administered, produces a general anesthesia including first an analgesic stage, followed by deep anesthesia with suppression of consciousness, respiratory paralysis, cerebral death and circulatory collapse. The stage of involuntary excitation that normally occurs between the analgesic and deep anesthesia stages is omitted when the recommended dosage of T-61® is properly injected. . . . The cortical encephalographic changes are typical of the anesthetic component alone. They occur almost immediately following proper administration and advance rapidly to cerebral death. The second component exerts its effect during the deep anesthesia stage, augmenting skeletal muscle relaxation and respiratory paralysis. Cerebral death occurs prior to circulatory collapse.

Animals euthanized with T-61®, when it is properly administered, do not experience anoxic pain, since the neural pharmacologic action of the anesthetic component is evident prior to apneusis." Id. (Emphasis added.)

According to the manufacturer, animals euthanatized with T-61 do not experience any pain associated with an inability to breathe because they are already unconscious as a result of the general anesthetic component. T-61 is intended exclusively for use as an euthanasia agent for dogs, cats, horses, mink, small laboratory animals, and birds. Id. The preferred method of administering T-61 is by intravenous injection. However, intrapulmonary or intracardiac injections may also be used under certain circumstances. Id. T-61 is not a controlled dangerous substance subject to extensive federal and state regulation because it does not contain regulated drug components. See, e.g., 21 U.S.C. §801 et seq.; Art. 27, §276 et seq. of the Maryland Code; AVMA Report, supra, at 68.

The veterinary medical literature describes T-61 as follows:

"T-61 is an injectable nonbarbiturate, nonnarcotic mixture of 3 drugs used to induce euthanasia. These drugs provide a combination of general anesthetic, curariform, and local anesthetic actions. Death results from severe CNS depression, hypoxia, and circulatory collapse. T-61 has been used in Germany since 1962 and became available in the United States soon thereafter. Because it is not currently listed as a controlled substance under federal drug regulations, it has gained popularity in recent years.

Advantages— ... (2) the terminal gasp which may accompany pentobarbital euthanasia is not evident with T-61.

Disadvantages— ... (3) except in the horse, if T-61 is injected at a rapid rate, the animal may appear to experience pain or discomfort immediately prior to becoming unconscious. ..." AVMA Report, supra, at 68 (emphasis added) (footnotes omitted).5

5 The manufacturer specifically warns against the rapid injection of T-61, adding: "The correct injection technique is a prerequisite to effect euthanasia without excitation or pain". Package Insert for T-61 Euthanasia Solution, American Hoechst Corporation, Animal Health Division (1980).

See also Hatch, supra, at 1292; Lumb, Doshi & Scott, A Comparative Study of T-61 and Pentobarbital for Euthanasia of Dogs, 172 J. Am. Vet. Med. Ass'n 149, 152 (1978). A review of the recent veterinary medical literature reveals relatively few references to T-61. Of the two scientific publications discussing this drug in conjunction with other euthanasia agents, it is significant that neither one classified T-61 as a "curariform drug". Compare AVMA Report, supra, at 68 and Hatch, supra, at 1292 with AVMA Report, supra, at 69 and Hatch, supra, at 1294.

Based on the manufacturer's package insert and the veterinary medical authorities cited above, 4, 4'-methylene-bis (cyclohexyl-trimethyl-ammonium iodide) has a curare-like effect insofar as it produces respiratory paralysis. However, T-61 contains another component that induces deep anesthesia prior to respiratory failure. Hence, the animal is unconscious before the curariform component takes effect. According to the scientific literature discussed above, the animal does not experience the sensation of suffocation and the intense anxiety that accompanies the administration of pure curariform drugs such as succinylcholine. See Hicks & Bailey, Jr., Succinylcholine Chloride as a Euthanatizing Agent in Dogs, 39 Am. J. Vet. Res. 1195, 1197 (1978).

III
Legislative Intent as Applied to T-61

Additional support for our conclusion that T-61 is not a "curariform drug", at least as that term is used in §59A, is found in the title of the legislation that enacted this statute. It is well-settled in Maryland that the title of an act may be considered to ascertain the legislative intent and purpose when the statute is of doubtful meaning. E.g., State Farm Mut. Auto. Ins. Co. v. Insurance Comm'r, 283 Md. 663, 674 n.3 (1978); Commission on Human Relations v. Mayor & City Council of Baltimore, 280 Md. 35, 41 (1977); State v. Wagner, 15 Md. App. 413, 422 (1972).

Section 59A was enacted by Chapter 342, Laws of Maryland 1979. The title of Chapter 342 describes that act as being:

"AN ACT concerning

Euthanasia of Dogs and Cats

FOR the purpose of prohibiting the killing of dogs and cats by certain methods; providing a penalty for violations; and generally relating to the humane killing of dogs and cats." (Emphasis added).

The title's references to "euthanasia" and "humane killing" suggest that the General Assembly intended only to prohibit those certain methods of killing dogs and cats that it considered inhumane.6 Thus, for example, the statute does not proscribe the use of euthanasia agents that induce immediate unconsciousness by depressing the central nervous system prior to death due to hypoxia (e.g., anesthetic gases, carbon dioxide, barbituric acid derivatives, chloral hydrate); these euthanasia agents are thus considered legal and, by implication, humane. Similarly, in our view, the use of T-61 is consistent with the statutory intent that euthanasia be induced by humane means.

6 The word "euthanasia" is derived from the Greek roots eu- meaning "well" and thanatos meaning "death" and is defined as "an easy and painless death." Webster's New World Dictionary 484 (2d college ed. D. Guralnik 1978).

When euthanasia is indicated for an animal, the predominant consideration is inducing a painless death. See AVMA Report, supra, at 60. According to veterinary medical authorities, animals do not experience pain if they are unconscious. As the AVMA Panel on Euthanasia observed in its latest report:

"The sensation of pain is initiated by damage to or intense stimulation of almost any part of the body. In tissues, pain receptors react to substances released when tissue is damaged. . . .

. . . Recognition of pain by an animal depends on impulses from pain receptors traversing pain pathways leading to the thalamus and cerebral cortex. For pain to be experienced, the cerebral cortex and subcortical structures must be functional. An unconscious animal does not experience pain because the cerebral cortex is not functioning. If the cerebral cortex is rendered nonfunctional by any means such as hypoxia, depression by drugs, electric shock, or concussion, pain is not experienced.

In an unconscious animal, stimuli that evoke pain will elicit reflex responses manifested by motor movement. For this reason, purposeful or nonpurposeful movements of an animal are not reliable indicators of cerebral pain reception. Conversely, an animal can experience pain, even though no body movements occur in response to painful stimuli, if the animal is given muscle paralyzing agents such as curare, succinylcholine, gallamine, pancuronium, nicotine, or decamethonium. These muscle paralyzing agents do not depress the cerebral cortex or thalamus." AVMA Report, supra, at 60 (emphasis added).

Although determining whether an animal is "conscious" poses some difficulties, veterinarians believe that measurement of electrical activity in the brain by means of an electroencephalogram ("EEG") can reveal whether an animal is experiencing pain:

"The humaneness of the euthanasia procedure has been related to the duration of consciousness; however, the state of consciousness is difficult to ascertain in animals. Investigations have shown that the electroencephalogram (EEG) of a conscious dog has a dominant frequency of 25 to 30 cycles per second (cps), whereas that of a deeply anesthetized dog is almost flat, with occasional bursts of 5 to 10 cps. Other work has shown that low-voltage fast activity (LVFA) or an 'activated EEG' is predominant during apprehension and periods of pain in the dog." Hicks & Bailey, Jr., supra, at 1195 (footnotes omitted).

Regarding the unsuitability of succinylcholine, a curariform drug, for euthanasia purposes, Hicks and Bailey, Jr. concluded:

"Comparison of events in anesthetized and nonanesthetized dogs revealed that cessation of cortical activity could be attributed to respiratory failure (apnea). Paralysis of the respiratory muscles, due to the depolarizing-blocking activity of succinylcholine chloride, has been shown to be the cause of death in these experimental animals. . . . Electroencephalograms did not indicate loss of consciousness as the waveform progressed from the normal awake waveform to activated EEG. The EEG became isoelectric from periods ranging from 360 to 540 [seconds] after injection. This response of the EEG indicates that the dogs dying in this matter are conscious for long periods, but the exact point of unconsciousness could not be ascertained from the data collected." Id. at 1197 (emphasis added) (footnote omitted).

In contrast, the authors of a comparative study of T-61 and pentobarbital, a barbituric acid derivative and widely accepted euthanasia agent for dogs,7 observed:

"A significant difference was not found between the 2 agents in the time necessary for the EEG to become isoelectric. However, pentobarbital-treated dogs had a mean time of 12 seconds longer than T-61-treated dogs before activity ceased." Lumb, Doshi & Scott, supra, at 150-51 (emphasis added).

7 The AVMA Panel summarized the effects of barbituric acid derivatives when used as euthanasia agents as follows:

"Barbiturates depress the entire central nervous system, but quantitatively, various areas are affected differently. Within seconds of intravenous administration, unconsciousness is induced which progresses to deep anesthesia. . . . Breathing stops from depression of the respiratory center, and cessation of heart action quickly follows. Direct action on the medulla accounts for respiratory depression when high dosages are given. Several barbiturates are acceptable, but pentobarbital sodium is most commonly used for euthanasia." AVMA Report at 68 (emphasis added).

Pentobarbital is a Schedule II controlled dangerous substance in Maryland. Art. 27, §279(b)d.4. Thus, it is subject to a number of restrictions governing its purchase and use.

The study states that the EEG was isoelectric (i.e., showing no variation in electric potential) after five minutes, indicating that the animal was dead. Id. at 150. Although pentobarbital is considered to be an "ideal" euthanasia agent for dogs, id. at 149, this study concluded:

"[B]oth T-61 and pentobarbital sodium induced euthanasia smoothly and without undesirable reactions. They thus fulfilled the prime requirement of such an agent, which is painless death.

T-61-treated dogs were injected more slowly and thus collapsed during the injection process. Pentobarbital was administered in a bolus at a faster rate than T-61; therefore, the dogs given pentobarbital collapsed after the injection was complete. The most striking difference in the effects of the 2 agents was the fact that pentobarbital did not maintain cardiac and respiratory arrest in 3 of the 12 dogs. Whether these dogs would have survived the initial injection alone is a matter for conjecture. Certainly, in clinical practice such a phenomenon does occasionally occur and is undesirable.

T-61 contains 3 chemically and pharmacologically different substances to provide a combination of general anesthetic, curariform, and local anesthetic actions. Euthanasia results from severe CNS depression, hypoxia, and circulatory collapse. It is probable that the general anesthetic alone ... is administered in sufficient quantity to cause euthanasia by CNS depression. Addition of the muscle relaxant . . . further assures that respirations cannot resume, as occurred with pentobarbital. Without testing each component of T-61 individually, the contributive action of each drug cannot be determined. In any event, the combination of drugs was highly effective and did not allow resumption of respiration." Id. at 151-52 (emphasis added).

Thus, T-61 appears to offer a slight advantage over pentobarbital in terms of preventing the resumption of respiration. Furthermore, there was no indication that the animals were conscious or experienced any pain when T-61 was administered.

Based upon the scientific literature discussed above, T-61 should not be considered a "curariform drug", as that term of art is used by the relevant scientific community, merely because it contains a curariform component. The manufacturer of T-61 and veterinary medical authorities agree that T-61 contains a curariform component; however, the overall effect of T-61 is not typical of pure curariform drugs. The distinction is that pure curariform drugs (e.g., succinylcholine, gallamine) do not immediately affect consciousness, and the animal is thus capable of experiencing pain or intense anxiety prior to death due to respiratory paralysis. The scientific literature quoted above reveals that T-61 immediately depresses the central nervous system causing loss of consciousness. The adjunct curariform component of T-61 does not take effect until after the animal is unconscious. Moreover, the anesthetic component alone may be lethal. Lumb, Doshi & Scott, supra, at 151. If euthanasia agents that depress the central nervous system are considered humane, then a combination agent such as T-61, whose immediate effect is virtually indistinguishable from other central nervous system depressants, should similarly be acceptable.

IV
Consequences of a Contrary Statutory Construction

The rules of statutory construction also permit us to examine the consequences flowing from choosing one interpretation of the statute over another and to adopt a construction that is in harmony with the general scheme of the enactment and that will assist in effectuating the legislative purpose. E.g., State v. Berry, 287 Md. 491, 496 (1980). Results that are unreasonable, illogical, or inconsistent with common sense should be avoided, and an interpretation should be given that will not lead to absurd or anomalous results. E.g., Kindley v. Governor, 289 Md. 620, 625 (1981); State v. Berry, supra, 287 Md. at 496; Comptroller v. John C. Louis Co., Inc., 285 Md. 527, 539 (1979). This rule applies to penal statutes, such as §59A. See Cider Barrel Mobile Home Court v. Eader, 287 Md. 571, 583 (1980).

Banning T-61 would lead to an illogical result for at least three reasons. First, if §59A were interpreted to preclude the use of T-61, the General Assembly would be prohibiting a euthanasia agent that (1) does not act in a manner typical of pure curariform drugs and (2) has the same immediate effect as other permissible euthanasia agents that depress the central nervous system and rapidly induce unconsciousness. Our interpretation, however, avoids this result while preserving the section's prohibition on the use of curariform drugs that do not depress the central nervous system prior to causing death (e.g., succinycholine, gallamine).

Second, T-61 meets most of the criteria established by the AVMA Panel for evaluating methods of euthanasia. These criteria are as follows:

"(1) Ability to produce death without causing pain; (2) time required to produce loss of consciousness; (3) time required to produce death; (4) reliability; (5) safety of personnel; (6) potential for minimizing undesirable psychologic stress; (7) compatibility with requirement and purpose; (8) emotional effect upon observers or operators; (9) economic feasibility; (10) compatibility with histopathologic evaluation; and (11) drug availability and abuse potential." AVMA Report, supra, at 64.

The scientific literature indicates that T-61 fulfills points (1), (2), (3), (4), (7), (8), (10),8 and (11) of the AVMA criteria. (None of the authorities reviewed discussed points (5), (6), or (9).) If T-61 is prohibited by §59A, it would place the General Assembly in the anomalous position of banning a euthanasia agent that meets most, if not all, of the AVMA's evaluation criteria.

8 If administered in larger than recommended doses, T-61 may adversely affect histopathologic evaluations. AVMA Report at 69.

Third, the General Assembly would be in the illogical position of prohibiting the use of one of only two drugs specifically recognized by the Bureau of Veterinary Medicine of the U.S. Food and Drug Administration as effective "for the humane euthanasia of animals without excitation or pain". 46 Fed. Reg. 23,232 (April 24, 1981) (amending 21 C.F.R. §522.900) (emphasis added).9 The rules of statutory construction dictate that such incongruous results be avoided.

9 A new animal drug application ("NADA") for T-61 received final approval from the Bureau of Veterinary Medicine of the U.S. Food and Drug Administration ("FDA") on October 15, 1976. 41 Fed. Reg. 45,547 (Oct. 15, 1976). An NADA must be approved by the FDA before the drug can be administered to animals in the United States.

Because we conclude that the underlying legislative intent of §59A was not to prohibit euthanasia agents such as T-61, we do not need to reach the issue of, nor need we express an opinion about, whether this statute would be unconstitutional under the Supremacy Clause, U.S. Const. art. VI, cl. 2, insofar as state legislation affecting the use of euthanasia agents like T-61 might have been preempted by federal regulation in the field. Cf. Pharmaceutical Soc'y of the State of N.Y., Inc. v. Lefkowitz, 454 F. Supp. 1175, 1178-80 (S.D.N.Y.), aff'd, 586 F.2d 953 (2d Cir. 1978) (preemption analysis applied to state statutes regarding generic drugs and drug labeling); Cosmetic, Toiletry & Fragrance Ass'n, Inc. v. Minnesota, 440 F. Supp. 1216, 1220-25 (D. Minn. 1977), aff'd per curiam, 575 F.2d 1256 (8th Cir. 1978) (preemption analysis applied to conflicting state legislation and federal regulation of aerosol product labeling). Nor do we express an opinion about whether §59A would unreasonably burden interstate commerce, violative of the Commerce Clause, U.S. Const. art. I, §8, cl. 3, if it were construed to prohibit the use of T-61 as a euthanasia agent. See generally 2 Am. Jur. 2d Administrative Law §219 (1962).

V
Conclusion

In summary, although the issue is not altogether free from doubt, it is our opinion that T-61 is not a "curariform drug" within the ambit of §59A for four reasons:

First, "curariform drugs", as that term of art is used by the relevant scientific community, connotes a class of euthanasia agents that are inhumane because they paralyze the animal's respiratory function without affecting consciousness. However, when T-61 is administered as prescribed, there is no evidence that the animal experiences any sensation of suffocation or intense anxiety that usually accompanies the administration of pure curariform drugs such as succinylcholine and gallamine.

Second, the effect of T-61 is not typical of pure curariform drugs, even though it contains an adjunct curariform component. However, T-61's general anesthetic component immediately induces unconsciousness before the curariform component takes effect to prevent the resumption of respiration.

Third, consonant with the express legislative purpose of advocating the humane killing of dogs and cats, the immediate effect of T-61 is virtually indistinguishable from other humane and widely accepted euthanasia agents that depress the central nervous system.

Fourth, banning T-61 would lead to absurd and illogical results because (1) the overall effect of this combination drug is not typical of pure curariform drugs, (2) it meets most, if not all, of the AVMA's criteria for acceptable euthanasia agents and is approved by that association for euthanasia purposes, and (3) T-61 is one of only two euthanasia agents specifically approved by the Bureau of Veterinary Medicine of the U.S. Food and Drug Administration as humane and effective.

Stephen H. Sachs, Attorney General
Ronald S. Gass, Assistant Attorney General
Avery Aisenstark
Principal Counsel,
Opinions and Advice