Substance Use

Note: Some medications mentioned in this chapter may not be available on the VHA National Formulary. Consult VA pharmacists for alternatives.

Background

• Substances frequently abused in the United States include alcohol, nicotine, cannabis, prescription medications (narcotics, sedatives, and many others), cocaine, heroin, methamphetamines, tranquilizers, hallucinogens, anabolic steroids, inhalants, and "club drugs."
• Club drugs include methylenedioxymethamphetamine (MDMA, or ecstasy), flunitrazepam (Rohypnol), gamma-hydroxybutyrate (GHB), and ketamine.
• The focus of this chapter is on recognition and management of abuse involving heroin, other opiates, and methamphetamine. Abuse of cocaine, cannabis, and club drugs will be addressed briefly.
• Alcohol misuse and tobacco use are discussed in separate chapters (see Alcohol Misuse and Smoking Cessation.)

Definitions

Addiction: a primary, chronic, neurobiologic disease, with genetic, psychosocial, and environmental factors influencing its development and manifestations. It is characterized by behaviors that include one or more of the following: impaired control over substance use, compulsive use, continued use despite harm, and craving.

Physical dependence: a state of adaptation that is manifested by a drug class-specific withdrawal syndrome that can be produced by abrupt cessation, rapid dose reduction, decreasing blood level of the drug, or administration of an antagonist.

Tolerance: a state of adaptation in which exposure to a drug induces changes that result in a diminution of one or more of the drug's effects over time.

Substance dependence: a maladaptive pattern of substance use, leading to clinically significant impairment or distress, manifested as tolerance (need for increased amounts of the substance or decreased effect with the same amount) or withdrawal symptoms.

Substance abuse: a maladaptive pattern of substance use that has become socially, legally, or occupationally problematic for an individual.

SUD: a more general term comprising substance dependence or abuse.

IDU: includes IV drug use, IM drug use, and skin popping. IDU can involve opiates, methamphetamines, cocaine, sedatives/tranquilizers, or other drugs.

Epidemiology

• Drug abuse is closely associated with HIV infection in the United States: 40-45% of injection drug users are HIV infected, and 25-30% of noninjection drug abusers are HIV infected.
• About 40% of people who are HIV infected are associated with IDU, either directly or by having an IDU sex partner.
• In the United States, 60% of injection drug users are men, 45% are white, 43% have completed high school, and 53% are employed.
• Comorbidities are common: 30% of injection drug users in the United States are PPD positive, 80-90% are infected with hepatitis C, 40% are infected with hepatitis B, and 60% use alcohol.
• Drug abusers are at high risk of unsafe sex practices. For example, cocaine abusers are more likely to involve themselves in prostitution and unsafe sex in order to obtain money for drugs.
• At least one third of drug abusers have an overt psychiatric comorbidity.

Substance Abuse, HIV Infection, and ART

• Cocaine use decreases CD4 cell production by as much as 3- to 4-fold and increases the rate of HIV viral replication by up to 20-fold.
• In a prospective cohort study, active drug use was strongly associated with underutilization of ART, nonadherence, and inferior virologic and immunologic responses to ART, compared with former drug use and nonuse of drugs.
• Methamphetamine and cocaine binges are associated with interruptions in ART adherence.
• A recent national survey showed that 23% of health providers for HIV-infected patients have a negative attitude toward treating HIV-infected IDU patients. These providers are less likely to prescribe ARVs to their IDU patients even when the patients meet criteria for starting ART.

Evaluation

There are many reasons to identify patients who abuse substances, and to try motivating them toward treatment. Unlike the strong evidence on effectiveness of brief interventions for alcohol misuse, there is little evidence from primary care settings that screening and brief interventions are effective for those with other drug-use disorders. Approaches that focus on the effects of substance abuse on the patient?s own health (eg, in terms of poor ART adherence, acquisition of infections) may be useful. See also Prevention for Positives.

Screening

At initial visit and at least annually thereafter: Ask all patients about any current or recent use of illicit drugs (in addition to alcohol and nicotine), including IDU, opioids, methamphetamines, cocaine, club drugs, illegally obtained prescription drugs, and legally obtained but misused prescription drugs. Check for comorbid psychiatric illnesses.

Management

• Goals for patients: Return to productive functioning.
• Goals for providers: Reduce stigma and treatment bias.
• Treatment includes helping the patient accept the role of having an illness, detoxification, treatment of comorbid conditions, maintenance of treatment, and relapse prevention.
• Treatment ideally involves a comprehensive program of behavioral interventions, though many patients may not accept referral.
• Comprehensive treatment may reduce drug abuse by 40-60%, reduce associated crime by 40-60%, and increase employment prospects by 40%.
• A comprehensive treatment program incorporates the expertise of medical providers, psychiatrists to assist with comorbid psychiatric conditions, social workers, housing counselors, case managers, and substance abuse counselors. Group therapy with peer support can also be an important component of treatment.
• For patients unwilling to undertake treatment, continue to address their substance use, focusing on reducing use or increasing readiness for drug cessation.

Brief Interventions for Patients Identified with SUD

Raise Importance

Ask: "On a scale of 1-10, how IMPORTANT is it for you to change your substance use?"

• "Why did you give it (number) and not a (lower number)?"
• "What would it take for you to give it a (higher number)?"

Raise Confidence

Ask: "On a scale of 1-10, how CONFIDENT are you that you can change successfully?"

• "Why did you give it (number) and not a (lower number)?"
• "What would it take for you to give it a (higher number)?"

Brief Interventions

Cannabis and Club Drugs

The effects of club drugs are less well-characterized. Here is an overview of the effects of cannabis and some common club drugs:

Pain Management in Patients with an SUD

Pain management should be in accordance with the principles of the VHA?s stepped care model for management of pain across the continuum of care, from acute to chronic.

• The prevalence of self-reported pain among HIV-infected patients ranges from 28-97%.
• HIV-infected patients with an SUD are more likely to be untreated or undertreated for pain.
• Pain management in SUD patients may be complicated by opiate tolerance.
• Clinician concerns about pain management in patients with an SUD include:
  • Drug seeking by patients
  • Diversion
  • Relapse to substance abuse
  • Legal repercussions
  • Inadequate knowledge or skills on the part of the clinician
  • Unavailability of specialists
• SUD patient concerns about pain management include:
  • Relapse to substance abuse
  • Anticipated physical discomforts (eg, thinking that medicines will be injected; fearing side effects)
  • Fearing accusations of malingering
  • Perceived "weakness" in taking medications for pain
• Appropriate evaluation of pain in the HIV-infected SUD patient includes:
  • An accurate and complete pain history, including results of previous evaluations; distinguishing between neuropathic and nonneuropathic pain may help guide therapy
  • Use of a numeric pain scale to assess and follow severity and response to therapy
  • Appropriate and complete evaluation to identify correctable causes of pain (eg, use of a neurotoxic medication in a patient complaining of painful neuropathy)
  • Accurate and complete documentation of findings via CPRS
• Principles of pain management in the HIV-infected SUD patient include:
  • Having a single provider prescribe all pain medications
  • Accurate and complete documentation of the rationale for the treatment used, including dosage, dose interval, amount prescribed, and refill procedures
  • If a patient has an active SUD, consultation with or referral to a treatment program
  • Agreement with the patient on goals of therapy:
    • In cases of acute pain, elimination of pain is a reasonable goal, with agreement on when the need for therapy will end
    • For chronic pain, the goal should be reasonable relief of pain with a maximum level of functioning
  • Use of specific rules ("contract") that addresses reports of lost medications, missed appointments etc, to promote accountability and decrease the risk of diversion or drug-seeking behavior.
  • Pretreatment agreement to random urine toxicology screens
  • Use of a stepwise approach to analgesia (see Pain Medications)
  • Use of nonpsychotropic pain medications, when possible, to achieve pain relief
  • When opiates are indicated, use the minimum dosage needed to relieve pain
  • Around-the-clock dosing is more effective than use as needed
  • Ensuring that adequate pain relief is obtained to prevent self-medication: Increasing dosages may be required if the underlying cause of pain (eg, malignancy) progresses or tolerance develops
  • Referral to a pain specialist for complex management issues or concerns over drug-seeking behavior

References

• AIDS Education & Training Centers National Resource Center. Recreational Drugs and Antiretroviral Therapy: a Guide to Interactions for Clinicians. Prepared by Urbina A, et al. November 2009. Accessed January 7, 2011
• American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Text Revision, 4th Edition. Washington D.C.: American Psychiatric Publishing; 2000.
• Basu S, Bruce RD, Barry DT, et al. Pharmacological pain control for human immunodeficiency virus-infected adults with a history of drug dependence. J Subst Abuse Treat. 2007 Jun; 32(4):399-409.
• Colfax G, Shoptaw S. The methamphetamine epidemic: implications for HIV prevention and treatment. Curr HIV/AIDS Rep. 2005 Nov;2(4):194-9.
• Erowid: a member-supported organization that provides access to diverse sources of information on psychoactive substances, including recreational drugs. Accessed January 7, 2011.
• Francis H. Substance abuse and HIV infection. Top HIV Med. 2003 Jan-Feb;11(1):20-4.
• Lum PJ, Tulsky JP. The medical management of opioid dependence in HIV primary care settings. Curr HIV/AIDS Rep. 2006 Nov;3(4):195-204.
• McNicholl I. HIV InSite Database of Antiretroviral Drug Interactions. San Francisco: UCSF Center for HIV Information. Accessed January 7, 2011.
• National Institute on Drug Abuse (NIDA): research and policy on the prevention and treatment of drug abuse and addiction. NIDA also has a website addressing substance abuse and HIV.
• National Institute on Drug Abuse (NIDA): research and policy on the prevention and treatment of drug abuse and addiction. NIDA also has a website addressing substance abuse and HIV.
• Prater CD, Zylstra RG, Miller KE. Successful pain management for the recovering addicted patient. Prim Care Companion J Clin Psychiatry. 2002 Aug; 4(4):125-131.
• The Management of Substance Use Disorders Working Group. VA/DoD Clinical Practice Guideline for the Management of Substance Use Disorders (Version 2.1). Washington, D.C.: Department of Veterans Affairs and the Department of Defense; 2009. Available at http://www.healthquality.va.gov. Accessed April 7, 2011.