Methamphetamine

Use of the illicit drug methamphetamine is a widespread public health issue in the U.S. and North America.¹ The allure of this drug is that it is cheap, easy to make, and provides a long-lasting high (e.g., 12 hours).^{1, 2} Methamphetamine has a chemical structure similar to amphetamine³ and is known by a myriad of street names, including “meth,” “speed,” “ice,” “chalk,” “crank,” “glass,” and “crystal.”^{3, 4} Its use is more prevalent in the U.S. West, Midwest, and South than in the Northeast, and while it may typically be thought of as affecting rural, young, White males and blue-collar workers, its use has spread to urban and suburban areas, as well as among college students and young professionals.^{1, 3}

As well as being a potent central nervous system stimulant that can cause permanent brain damage, methamphetamine use has also been associated with severe oral health effects.^{1, 3, 4} Awareness of methamphetamine’s adverse oral health effects and the treatment considerations for users of this drug can help dental professionals identify oral conditions that may be attributable to methamphetamine use.

Methamphetamine can be smoked, snorted, injected, or taken orally.^{4, 5} Typically, it is a bitter-tasting powder that readily dissolves in water or alcohol.³ Another common form of the drug is a clear, chunky crystal. This is the form known as “ice” or “crystal meth” and it is smoked in a manner similar to crack cocaine.³ Methamphetamine can also be in the form of small, brightly colored tablets, sometimes combined with caffeine; these pills are often called by their Thai name, yaba.^{3, 4}

Methamphetamine stimulates release and blocks reuptake of neurotransmitters called monoamines (dopamine, norepinephrine and serotonin) in the brain.³ Several areas of the brain are affected: the nucleus accumbens, prefrontal cortex, and striatum.^{3, 6}

By altering the levels of neurotransmitters in the brain, including dopamine, methamphetamine causes feelings of pleasure and euphoria.^3,7 Methamphetamine is a neurotoxin and potent stimulant, which can also cause cerebral edema and hemorrhage, paranoia and hallucinations.³ Short-term effects include vomiting, insomnia, hyperactivity, decreased appetite, increased respiration and tremors.^{2, 5} Long-term effects can include psychological addiction, stroke, violent behavior, anxiety, confusion, paranoia, auditory hallucination, mood disturbances, and delusions.^{2, 5} Methamphetamine use can eventually cause depletion of monoamines in the brain, which can have an effect on learning.^{3, 8, 9}

Systemic effects of methamphetamine may include an increase in blood pressure and rapid heartbeat, due to cardiac stimulation, especially with high doses.^{2, 5} In addition, methamphetamine may produce cardiac arrhythmias.⁵ Other systemic effects include: shortness of breath, hyperthermia, nausea, vomiting and diarrhea.^{2, 5}

The oral effects of methamphetamine use can be one of the most visible and devastating consequences of drug use.^{3, 10} The severe caries associated with use of methamphetamine is referred to colloquially as “meth mouth” or “crank decay” and is said to resemble early childhood caries.^{1, 7, 10-14} A distinct and often severe pattern of decay can often be seen on the buccal smooth surface of the teeth at the cementoenamel junction and the interproximal surfaces of the anterior teeth.^{7, 13-16} Other clinical signs of methamphetamine use include severe xerostomia, gingivitis/periodontitis, and missing or fractured teeth.^{7, 15, 17-19}

A propensity score analysis estimated that methamphetamine abusers were twice as likely to have untreated caries, 4 times as likely to have any experience of caries, and twice as likely to have 2 or more decayed, missing, or filled teeth, compared to a general dental population.¹⁴ Other research has shown that, contrary to common perception, individuals who smoke methamphetamine do not have higher rates of dental disease than those who snort or inject the drug.^{16, 20, 21}

As a sympathomimetic amine, methamphetamine stimulates the sympathetic nervous system, acting on adrenergic receptors and causing decreased salivary flow, leading to xerostomia and increased propensity for tooth decay.^1-5,21 Concomitant drug use, e.g., cigarette smoking and/or alcohol consumption, can also exacerbate xerostomia.¹ Methamphetamine users who have poor oral hygiene habits may further exacerbate the problem by allowing the build-up of plaque and cariogenic bacteria to continually metabolize sugar into acids.^{1, 20, 22} Individuals using methamphetamine may also consume large quantities of carbonated, sugared soda to both quench thirst and satisfy a craving for sweets.^{1, 20, 22}

Methamphetamine abuse may be associated other negative orofacial conditions including bruxism, grinding/clenching, disorders of the temporomandibular joint, myofacial pain, and trismus.^{1, 5, 7, 21} Xerostomia also may contribute to gingival inflammation and infections such as candidiasis, glossitis, and cheilitis.^{1, 7}

The following may indicate possible methamphetamine use:

• Unaccounted for and accelerated decay in teenagers and young adults.
• Distinctive pattern of decay on the buccal smooth surface of the teeth and the interproximal surfaces of the anterior teeth.
• Malnourished appearance in heavy users, because methamphetamine acts as an appetite suppressant.

When dental health-care providers suspect methamphetamine use, it may be appropriate to:^{1, 2, 7, 21, 23}

• As with all patients, complete a comprehensive oral examination that includes taking a thorough dental and medical history.
• Express concern regarding the dental findings.
• Consider employing preventive measures, such as topical fluorides.
• Encourage consumption of water, rather than sugar-containing carbonated beverages.
• Be cautious when administering local anesthetics with a vasoconstrictor, sedatives or general anesthesia, nitrous oxide, or when prescribing narcotics.

For patients who are receptive to a medical consult, a dental practice may wish to have the phone number of a local physician, clinic or substance abuse rehabilitation facility available and be familiar with their protocol, so that the patient can be told what to expect.

One of the fastest and easiest ways to find out about the treatment resources in your community may be to ask local emergency room staff. They may keep current information on local public and private treatment programs and professionals. State dental society well-being committee members may be familiar with such resources, as well. State governments may have a division for addiction services in the state, and may make that information available on websites. In addition, information can be found at http://findtreatment.samhsa.gov.

1. Heng CK, Badner VM, Schiop LA. Meth mouth. N Y State Dent J 2008;74(5):50-1.
2. Curtis EK. Meth mouth: a review of methamphetamine abuse and its oral manifestations. Gen Dent 2006;54(2):125-9; quiz 30.
3. Klasser GD, Epstein J. Methamphetamine and its impact on dental care. J Can Dent Assoc 2005;71(10):759-62.
4. Frese PA, McClure E. Methamphetamine: Implications for the dental team. Proctor & Gamble.  Accessed July 12, 2023.
5. National Institute on Drug Abuse. Research Report Series:  Methamphetamine (NIH Publication No. 13-4210). National Institutes of Health.  Accessed July 12, 2023.
6. U.S. National Institute on Drug Abuse (NIDA). Mind Matters: The Body's Response to Methamphetamine (NIH Publication No. 19-DA-8074). National Institutes of Health.  Accessed July 12, 2023.
7. Nassar P, Ouanounou A. Cocaine and methamphetamine: Pharmacology and dental implications. Can J Dent Hyg 2020;54(2):75-82.
8. Belcher AM, O'Dell SJ, Marshall JF. Impaired object recognition memory following methamphetamine, but not p-chloroamphetamine- or d-amphetamine-induced neurotoxicity. Neuropsychopharmacology 2005;30(11):2026-34.
9. Daberkow DP, Kesner RP, Keefe KA. Relation between methamphetamine-induced monoamine depletions in the striatum and sequential motor learning. Pharmacol Biochem Behav 2005;81(1):198-204.
10. Brown RE, Morisky DE, Silverstein SJ. Meth mouth severity in response to drug-use patterns and dental access in methamphetamine users. J Calif Dent Assoc 2013;41(6):421-8.
11. Howe AM. Methamphetamine and childhood and adolescent caries. Aust Dent J 1995;40(5):340.
12. McGrath C, Chan B. Oral health sensations associated with illicit drug abuse. Br Dent J 2005;198(3):159-62; discussion 47; quiz 74.
13. Shaner JW. Caries associated with methamphetamine abuse. J Mich Dent Assoc 2002;84(9):42-7.
14. Shetty V, Harrell L, Clague J, et al. Methamphetamine Users Have Increased Dental Disease: A Propensity Score Analysis. J Dent Res 2016;95(7):814-21.
15. Shetty V, Harrell L, Murphy DA, et al. Dental disease patterns in methamphetamine users: Findings in a large urban sample. J Am Dent Assoc 2015;146(12):875-85.
16. Shetty V, Mooney LJ, Zigler CM, et al. The relationship between methamphetamine use and increased dental disease. J Am Dent Assoc 2010;141(3):307-18.
17. Spolsky VW, Clague J, Murphy DA, et al. Periodontal status of current methamphetamine users. J Am Dent Assoc 2018;149(3):174-83.
18. Spolsky VW, Clague J, Shetty V. Cohort study of HIV-positive and -negative methamphetamine users. J Am Dent Assoc 2018;149(7):599-607.
19. Yazdanian M, Armoon B, Noroozi A, et al. Dental caries and periodontal disease among people who use drugs: a systematic review and meta-analysis. BMC Oral Health 2020;20(1):44.
20. Clague J, Belin TR, Shetty V. Mechanisms underlying methamphetamine-related dental disease. J Am Dent Assoc 2017;148(6):377-86.
21. Teoh L, Moses G, McCullough MJ. Oral manifestations of illicit drug use. Aust Dent J 2019;64(3):213-22.
22. Smit DA, Naidoo S. Oral health effects, brushing habits and management of methamphetamine users for the general dental practitioner. Br Dent J 2015;218(9):531-6.
23. Venker D. Crystal methamphetamine and the dental patient. Iowa Dent J 1999;85(4):34.

American Society of Addiction Medicine

Mayo Clinic: Drug Addiction (Substance Use Disorder)

National Institute on Drug Abuse (NIDA):

• Drugs of Abuse (click on “Methamphetamine (Crystal/Meth)”)
• Methamphetamine
• Methamphetamine Research Report

PBS Frontline: The Meth Epidemic

U.S. Drug Enforcement Administration (DEA): Drugs of Abuse 2020 Edition (page 66)

Online Continuing Education (offered by Crest/Oral-B): Methamphetamine: Implications for the Dental Team (PDF)