The Use of Compound Topical Anesthetics a Review

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CLINICAL PRACTICE CRITICAL REVIEW

The use of compound topical anesthetics A review

Neal D. Kravitz, DMD, MS

ompounding is the process A D by which the pharmacist A ABSTRACT J or doctor combines, mixes ✷ ✷ ®

or alters pharmaceuticals C

O or ingredients to create a Background. The author reviewed the history of, N I

T T

I A custom-madeC medication in accor- federal regulations regarding, risks of and adverse N U C 1 I U dance with a prescription. Pharma- drug reactions of five compound topical anesthetics: A N G E D R 2 ceutical compounds in the form of tetracaine, adrenaline/epinephrine and cocaine (TAC); TICLE anti-inflammatories, mouthrinses, lidocaine, adrenaline/epinephrine and tetracaine (LET); lidocaine, toothpastes, antibiotic preparations, tetracaine and phenylephrine (TAC 20 percent Alternate); lidocaine, soaps, electrolyte troches, bleaching prilocaine and tetracaine (Profound); and lidocaine, prilocaine, tetracaine gels and strong topical anesthetics and phenylephrine with thickeners (Profound PET). are commonplace in dentistry. In Types of Studies Reviewed. The author reviewed clinical trials, particular, compound topical anes- case reports, descriptive articles, and U.S. Food and Drug Administration thetics are applied to patients by (FDA) regulations and recent public advisory warnings regarding the fed- pediatric dentists for restorative eral approval of and risks associated with the use of compound topical procedures, by periodontists for anesthetics. scaling and root planing procedures, Results. Compound topical anesthetics are neither FDA-regulated nor by orthodontists for soft-tissue laser -unregulated. Some compounding pharmacies bypass the new FDA drug surgery and placement of ortho- approval process, which is based on reliable scientific data and ensures dontic temporary anchorage devices that a marketed drug is safe, effective, properly manufactured and accu- (TADs), and by oral surgeons for rately labeled. Two deaths have been attributed to the lay use of com- facial rejuvenating procedures. In pound topical anesthetics. In response, the FDA has announced the 2006, however, several U.S. Food strengthening of its efforts against unapproved drug products. and Drug Administration (FDA) Clinical Implications. Compound topical anesthetics may be an advisory reports were issued effective alternative to local infiltration for some minimally invasive regarding the potential hazards of dental procedures; however, legitimate concerns exist in regard to their using compound topical anesthetics. safety. Until they become federally regulated, compound topical anes- In January 2007, I conducted a thetics remain unapproved drug products whose benefits may not out- search on PubMed to identify weigh their risks for dental patients. English-language, full-text articles Key Words. Topical anesthetics; U.S. Food and Drug Administration; published from Jan. 1, 1980, compounding. through Dec. 31, 2006. The search JADA 2007;138(10):1333-9. terms I used were “topical,” “anesthetic,” “compound,” “pharmaceu- Dr. Kravitz was an orthodontic resident, Department of Orthodontics, University of Illinois at Chicago College of Dentistry, when this article was written. He now is in private practice in Chantilly, Va. tical” and “Food Drug Administra- Address reprint requests to Dr. Kravitz at 6017 Makely Drive, Fairfax Station, Va. 22039, e-mail tion.” I also searched for relevant “[email protected]”.

articles, using the reference lists of already iden- the status of pharmacy compounding under fed- tified articles. eral law.3 Under section 503A of the FDAMA, In this article, I review the history, regula- drug products that are compounded on a cus- tions, recent FDA warnings and life-threatening tomized basis are exempt from the FDA’s new side effects of compound topical anesthetics. I drug approval requirements, under the provision examine clinical trials, case reports, descriptive that the provider does not advertise these prod- articles, FDA regulations and recent public advi- ucts to the public.2 In 2002, the U.S. Supreme sory warnings regarding the federal approval and Court ruling in Thompson, Secretary of Health risks associated with the use of compound topical and Human Services, et al., v. Western States anesthetics. Medical Center, et al., invalidated the provisions of section 503A under constitutional violation of PHARMACEUTICAL COMPOUNDING commercial free speech. Today, drug products Pharmaceutical compounding has been part of compounded at pharmacies are neither FDA- pharmacy practice since its origins. Before syn- regulated nor -unregulated (Table 1).4 thetic and premade pharmaceuticals were avail- Abuse and violation of FDA policy. Many able, physicians would write prescriptions that large compounding pharmacies have sought local pharmacists would compound to produce shelter under this murky federal status, and their capsules, tablets or suspensions. Industrial drug practices are more consistent with those of drug manufacturing, however, was able to produce manufacturers.5 For example, some of these large drugs more efficiently and in bulk quantities. compounding pharmacies routinely produce bulk This led to the decline in compounding at local quantities of compound pharmaceuticals before pharmacies, which could not compete on the same receiving a prescription. According to the law, scale. Today, there has been a re-emergence of however, compounding may be done only for the larger, multicenter compounding pharmacies that needs of individual patients.4 provide hundreds of custom-made medical, dental To date, the FDA defers to state authorities and veterinary medications. regarding violations of FDAMA related to phar- Pharmaceutical compounding is not the same macy compounding. For significant violations of as drug manufacturing. Drug manufacturing is 21 USC §351 (adulterated drugs and devices); defined as the production, preparation, propaga- §352 (misbranded drugs and devices) and §355 tion, processing and packaging of a device or (new drugs) of FDAMA, the FDA may initiate reg- labeling of the commercial container.2 Unlike cus- ulatory action with seizure, injunction, prosecu- tomized compound pharmaceuticals, manufac- tion or a combination thereof. tured drug products are mass-produced and feder- Recent FDA warning regarding patients’ ally regulated under the Federal Food Drug and use of compound topical anesthetics. On Dec. Cosmetic Act. 5, 2006, the FDA issued a public health advisory FDA approval of pharmaceutical com- alert about the potential life-threatening side pounds. Through the early 20th century, several effects of compound topical anesthetics.6 Exposure worthless and often deadly elixirs were being to high concentrations of local anesthetics can mass-produced and distributed throughout the lead to serious adverse reactions, including anes- United States. The Elixir Sulfanilamide incident, thetic overdose, seizures, irregular heartbeats in which more than 100 people died after taking a and death. The FDA issued warnings to five legal, but toxic, drug in 1937, prompted President firms—Triangle Compounding Pharmacy (Cary, Franklin Delano Roosevelt to sign the Food, N.C.), University Pharmacy (Salt Lake City), Drug, and Cosmetic Act on June 25, 1938 (Table Custom Scripts Pharmacy (Tampa, Fla.), Hal’s 1). This act brought cosmetic and medical devices under federal control. However, the 1938 act was aimed at regulating industrial manufacturers, ABBREVIATION KEY. CPG: Compliance Policy Guide. not the neighborhood compounding pharmacy, FDA: U.S. Food and Drug Administration. which allowed compounding to continue as a FDAMA: Food and Drug Administration Moderniza- normal function of the profession for almost tion Act. LET: Lidocaine, adrenaline/epinephrine and 60 years. tetracaine. PABA: Para-aminobenzoic acid. The Food and Drug Administration Moderniza- TAC: Tetracaine, adrenaline/epinephrine and cocaine. tion Act (FDAMA) of 1997 attempted to clarify TADs: Temporary anchorage devices.

TABLE 1 Web sites addressing the regulation of pharmaceutical compounding.

TITLE WEB SITE

U.S. FDA* Home Page www.fda.gov/default.htm

Federal and Legal Rulings The 1938 Food, Drug, and Cosmetic Act www.fda.gov/oc/history/historyoffda/section2.html

FDA Modernization Act of 1997 www.fda.gov/oc/fdama/fdamapln/fdamapln.pdf

Legal Rulings Medical Center Pharmacy v. Gonzalez (2006) www.ncpanet.org/pdf/legal_med_center_pharm_vs_gonzales_order.pdf

Thompson, Secretary of Health and Human www.fda.gov/cder/pharmcomp/supremeCourt.pdf Services, et al., v. Western States Medical Center, et al (2002)

Western States Medical Center, et al., www.fda.gov/cder/pharmcomp/westappl.pdf v. Donna E. Shalala, et al. (2001)

Guidance for Industry Compliance Policy Guides Manual www.fda.gov/OHRMS/DOCKETS/98fr/02D-0242_gdl0001.pdf

Marketed Unapproved Drugs—Compliance www.fda.gov/cder/Guidance/6911fnl.pdf Policy Guide

Guide to Inspections of Topical Drug www.fda.gov/ora/Inspect_ref/igs/topic.html Products

Pharmacy Compounding Advisory www.fda.gov/cder/pharmcomp/advisorycommittee.htm Committee

FDA Public Advisory Warnings Warnings for Makers of Compounded Pain www.fda.gov/fdac/features/2007/207_compound.html Products

FDA Public Health Advisory www.fda.gov/cder/drug/advisory/topical_anesthetics.htm

Warning Letters and Notice of Violation www.fda.gov/cder/warn/ Letters to Pharmaceuticals Companies

* FDA: U.S. Food and Drug Administration.

Compounding Pharmacy (San Diego) and the old woman on Nov. 1, 2004. Both women lapsed New England Compounding Center (Fram- into comas and died from lidocaine toxicity after ingham, Mass.)—to stop them from compounding applying the topical anesthetic to their legs and and distributing standardized versions of topical wrapping them in cellophane before laser hair anesthetic creams. The anesthetics, which con- removal surgery. tained high concentrations of local anesthetics Compliance policy guide. In June 2006, the including lidocaine, tetracaine, benzocaine and FDA issued the Marketed Unapproved Drugs— prilocaine, were being marketed for general dis- Compliance Policy Guide (CPG),8 which outlines a tribution rather than being formulated for the prioritized, risk-based enforcement approach that specific medical needs of individual patients encourages compounding pharmacies to comply (Table 2). with the drug-approval process and ensure the According to the FDA, there have been at least safety and efficacy of their marketed products. two nonfatal reactions and two deaths attributed The issuance of the CPG was intended to provide to patients’ being given topical compound anes- notice that any product that is being marketed thetics to apply on their own.7 The compound top- illegally is subject to FDA enforcement action at ical anesthetic Lasergel Plus 10/10 (compounded any time. The highest priority will be given to by Triangle Compounding Pharmacy) was asso- drugs with potential safety risks, drugs that lack ciated with the death of a 22-year-old woman on evidence of effectiveness and health fraud drugs. Jan. 5, 2005. The compound topical anesthetic The FDA intends to evaluate whether justifica- Photocaine Gel (compounded by University Phar- tion exists to exercise enforcement on a case-by- macy) was associated with the death of a 25-year- case basis.

DERMAL COMPOUND TOPICAL caine and phenylephrine (TAC 20 percent ANESTHETICS Alternate, Professional Arts Pharmacy, Lafayette, La.). Practitioners should be familiar with the histor- LET. LET is a compound topical gel containing ical contributions of two popular compound 4 percent lidocaine, 0.1 percent epinephrine and dermal topical anesthetics: tetracaine, adrena- 0.5 percent tetracaine.11 It was created as a safer, line/epinephrine and cocaine (TAC) and lidocaine, more cost-effective alternative to TAC; it substi- adrenaline/epinephrine and tetracaine (LET). tutes lidocaine for cocaine. It is used primarily as TAC. TAC is a compound topical gel of 0.5 per- a dermal anesthetic for the emergency pediatric cent tetracaine, 0.05 percent epinephrine and 11.8 population. Early recommendations for LET use percent cocaine.9 It was the first topical anesthetic were to avoid mucosal contact; however, its active mixture found to be effective for use in simple ingredients are identical to those in TAC 20 per- suturing to the face and scalp.9 The use of TAC gel cent Alternate. no longer is supported in the literature owing to the general concern about toxicity, expense and MUCOSAL COMPOUND TOPICAL ANESTHETICS federal regulatory issues involving a restricted narcotic.10,11 TAC often is confused with the Two compound topical anesthetics used during mucosal anesthetic compound lidocaine, tetra- placement of orthodontic TADs and soft-tissue

TABLE 2 Compound topical anesthetics that received a warning from the U.S. Food and Drug Administration in 2005.

COMMON NAME ACTIVE INGREDIENTS* COMPOUNDING PHARMACY

Lasergel 10 percent lidocaine, 10 percent Triangle Compounding tetracaine Pharmacy (Cary, N.C.)

Lasergel Plus 10/10† 10 percent lidocaine, 10 percent tetracaine, 0.5 percent phenylephrine

Tetracaine Lollipops Tetracaine hydrochloride

Photocaine Gel‡ 6 percent lidocaine; 6 percent University Pharmacy (Salt tetracaine Lake City)

Anesthetic Skin Lotion 10 percent lidocaine, 2 percent Hal’s Compounding Pharmacy prilocaine (San Diego)

Anesthetic Skin Gel 3+ Lidocaine, prilocaine, tetracaine

Tetracaine 6% in DMSO§ Gel 6 percent tetracaine, DMSO

Triple Kwick Anesthetic Gel Benzocaine, lidocaine, tetracaine

Kwick Anesthetic Gel Benzocaine, lidocaine, tetracaine, DMSO

N*E*W Topical Anesthetic 30 percent lidocaine, 2 percent prilocaine, 4 percent tetracaine

Lidocaine and Tetracaine Demi Gel Lidocaine, tetracaine

Extra Strength Triple Anesthetic 20 percent benzocaine, 6 percent New England Compounding Cream lidocaine, 4 percent tetracaine Center (Framingham, Mass.)

Betacaine LA Ointment 15 percent fidocaine, 5 percent Custom Scripts Pharmacy prilocaine; phenylephrine (Tampa, Fla.)

Betacaine Plus Ointment 15 percent lidocaine, 5 percent prilocaine

* The concentration of anesthetic is provided if known. † Lasergel Plus 10/10 (compounded by Triangle Compounding Pharmacy) has been associated with the death of a 22-year-old woman on Jan. 5, 2005. ‡ Photocaine Gel (compounded by University Pharmacy) has been associated with the death of a 25-year-old woman on Nov. 1, 2004. § DMSO: Dimethyl sulfoxide.

A B

Figure 1. A. Application of a lidocaine, tetracaine and phenylephrine compound (TAC 20 percent Alternate) before the placement of a temporary anchorage device. B. Immediately after placement of the temporary anchorage device.

A B

Figure 2. A. Application of a lidocaine, tetracaine and phenylephrine compound (TAC 20 percent Alternate) before laser surgery in preparation for the placement of veneers. B. Localized tissue irritation after prolonged application of the topical anesthetic. laser surgery in the United States are TAC 20 2.5 percent prilocaine; AstraZeneca Pharmaceuti- percent Alternate and a lidocaine, prilocaine and cals, Wilmington, Del.), which is used to induce tetracaine mixture (Profound)12-14 (Figures 1 and dermal anesthesia before venipuncture, and 2). These “named” topical anesthetics are com- Oraqix (2.5 percent lidocaine, 2.5 percent prilo- pounded formulations, and they should not be caine; Dentsply Pharmaceutical, York, Pa.), mistaken for regulated, manufactured drugs. which is applied within the gingival sulcus before TAC 20 percent Alternate. TAC 20 percent scaling and root planing. Alternate is a compound topical gel containing An improved version of the original compound, two anesthetic agents (20 percent lidocaine and 4 Profound PET (sold as Profpet by Steven’s Phar- percent tetracaine), one vasoactive agent (2 per- macy, Costa Mesa, Calif.) contains 2 percent cent phenylephrine) and seven inactive ingredi- phenylephrine and various inactive ingredients ents that provide structure and give taste to the such as methylcellulose for greater viscosity. gel. Tetracaine is a long-acting ester that is Application and storage. The dosage and included in the anesthetic to provide more pro- duration of dental compound topical anesthetics found anesthesia. The product’s name—TAC 20 varies according to the patient and region of percent Alternate—is a misnomer; although it is application. The manufacturer’s recommended named after TAC gel, TAC 20 percent Alternate dosage for Profound, Profound PET and TAC 20 does not contain any cocaine. percent Alternate typically is 2 milliliters applied Profound and Profound PET. Profound is a for two to three minutes.12,14 The thick, attached compound topical gel containing three anesthetic tissue of the palatal slope may require prolonged agents: 10 percent lidocaine, 10 percent prilocaine application for adequate anesthesia. Peak anes- and 4 percent tetracaine. Profound was developed thesia usually is reached after five minutes and originally for use in soft-tissue laser surgery.14 Its lasts approximately 25 to 30 minutes.12,14 formulation is based on two FDA-approved topical Compound topical anesthetics may be stored at anesthetics: EMLA cream (2.5 percent lidocaine, room temperature. Since phenylephrine makes

ciated with a higher inci- dence of allergic reactions than are other local anesthetics, such as lidocaine.15 Ester-type anesthetics are metabolized in the blood- stream by the enzyme pseudocholinesterase. Atyp- ical pseudocholinesterase activity (frequency, 1 per 2,800 people) is an inherited Figure 3. Two photographs of a lidocaine, tetracaine and phenylephrine compound ordered enzyme abnormality that from two different locations of the same compounding pharmacy taken the day the anesthetics results in a person’s were delivered. inability to hydrolyze ester the topical anesthetic light sensitive with a shelf anesthetics and chemically related drugs such as life of 90 days, those that contain phenylephrine succinylcholine.15 (TAC 20 percent Alternate and Profound PET) Amide-type anesthetics (lidocaine, prilocaine) should not be exposed to light unnecessarily.14 undergo metabolic breakdown in the liver and, Risks associated with compound topical therefore, are contraindicated in patients with anesthetics. The risks associated with the use of poor liver function such as cirrhosis.15 Specifically, compound topical anesthetics should be under- amide-type anesthetics that contain prilocaine stood clearly by clinicians. Some of these risks are are contraindicated in patients with glucose-6- that phosphate dehydrogenase deficiency or congenital dthey are packaged in vials and tubes, which or idiopathic methemoglobinemia. Prilocaine use makes accurate dosing difficult; can lead to elevated levels of methemoglobin, dthe maximum recommended dosage is which decreases the ability of erythrocytes to unknown, because compound topical anesthetics transport oxygen, resulting in rapid cyanosis.15 are meant to be custom-produced and used by In addition, direct-acting sympathomimetic only one patient; agents such as phenylephrine, which can be found dthere is a narrow difference between the in TAC 20 percent Alternate and Profound PET, optimal therapeutic dose of these products and can cause serious adverse events related to hyper- the doses at which they become toxic (that is, they tension and vasoconstriction. have a low therapeutic index); The most common localized adverse reaction to dthey may vary in their composition, the quality compound topical anesthetics are tissue irritation of the mixture and the strength of anesthesia (usually after prolonged application) and transi- (Figure 3); tory taste perversion. dthey often are labeled improperly and the labels fail to warn the user of risks and adverse CONCLUSIONS reactions; In 2004, the then-editor of JADA, Dr. Marjorie K. dthey regularly include several active anes- Jeffcoat, offered simple advice to her readers with thetics, often resulting in a mixture of esters and regard to the use of pharmaceutical compounds: amides. “don’t do it.”4 She anticipated the escalation of Contraindications and adverse drug reac- industry abuse, increased federal regulation and tions. Clinicians who use compounded pharma- enforcement. Notwithstanding the recent FDA ceuticals should be aware of the product’s phar- warnings, there still arguably is a place for macology and any contraindications. doctor-prescribed, doctor-applied compound topi- Ester-type anesthetics (benzocaine, tetracaine) cal anesthetics for use on an individualized basis. are contraindicated in patients with para- Until these drugs become federally regulated, aminobenzoic acid (PABA) allergy or atypical however, the large-scale production of some pseudocholinesterase activity. PABA is a meta- remains an end-run on manufacturing require- bolic by-product of ester anesthetics that is ments, and their routine use remains a question- known for its high allergic potential, which can able therapeutic practice that may have life- lead to anaphylactic shock. Tetracaine is asso- threatening consequences. ■

1. United States Pharmacopeial Convention. Good compounding gov/cder/drug/advisory/topical_anesthetics.htm”. Accessed Aug. 28, practices. In: The United States Pharmacopeia: USP 28: the National 2007. Formulary: NF 23: by authority of the United States Pharmacopeial 8. U.S. Department of Health and Human services, Food and Drug Convention, Inc., meeting at Washington, April 12-16, 2000. Rockville, Administration, Center for Drug Evaluation and Research. Guidance Md.: United States Pharmacopeial Convention; 2004: 2620, 2457. for FDA staff and industry: Marketed Unapproved Drugs—Compliance 2. Department of Health and Human Services, Food and Drug policy guide, Sec. 440.100 Marketed new drugs without approved NDAs Administration. Registration of producers of drugs and listing of drugs or ANDAs. Available at: “www.fda.gov/cder/guidance/6911fnl.pdf”. in commercial distribution—21 CFR part 207 (OMB Control Number Accessed Aug. 29, 2007. 0910-0045)—extension. Fed Regist 2000;65(213):65858-9. 9. Pryor GJ, Kilpatrick WR, Opp DR. Local anesthesia in minor lacer- 3. Food and Drug Administration Moderization Act of 1997, 21 USC ations: topical TAC vs lidocaine infiltration. Ann Emerg Med 1980; §353A (1997). 9(11):568-71. 4. Jeffcoat MK. Eye of newt, toe of frog: drug compounding: proceed 10. Calatayud J, Gonzalez A. History of the development and evolu- with caution. JADA 2004;135(5):546-8. tion of local anesthesia since the coca leaf. Anesthesiology 2003;98(6): 5. U.S. Food and Drug Administration. Compliance Policy Guide: 1503-8. Compliance Policy Guidance for FDA Staff and Industry—Sec. 11. Kundu S, Achar S. Principles of office anesthesia, part II: topical 460.200, Pharmacy compounding. Available at: “www.fda.gov/ora/ anesthesia. Am Fam Physician 2002;66(1):99-102. compliance_ref/cpg/cpgdrg/cpg460-200.html”. Accessed Aug. 7, 2007. 12. Kravitz ND, Kusnoto B. Placement of mini-implants with topical 6. U.S. Food and Drug Administration. FDA news: FDA warns five anesthetic. J Clin Orthod 2006;40(10):602-4. firms to stop compounding topical anesthetic creams. Available at: 13. Kravitz ND, Kusnoto B, Tsay TP, Hohlt WF. The use of tempo- “www.fda.gov/bbs/topics/NEWS/2006/NEW01516.html”. Accessed Aug. rary anchorage devices for molar intrusion. JADA 2007;138(1)56-64. 28, 2007. 14. Graham JW. Profound, needle-free anesthesia in orthodontics. J 7. U.S. Food and Drug Administration. FDA public health advisory: Clin Orthod 2006;40(12):723-4. Life-threatening side effects with the use of skin products containing 15. Malamed SF. Handbook of local anesthesia. St. Louis: Mosby; numbing ingredients for cosmetic procedures. Available at: “www.fda. 1997:24-36.