Substance Misuse and Addiction

• Substance misuse can result in physical dependence, psychological dependence, habituation, and addiction.

Commonly Misused Substances

• Opioids: heroin, codeine phosphate, hydrocodone, hydromorphone, meperidine hydrochloride, morphine, fentanyl, oxycodone
• Stimulants: racemic amphetamine, dextroamphetamine, methamphetamine, cocaine
• Depressants: Benzodiazepines, barbiturates, marihuana
• Other: Alcohol, anabolic steroids, dextromethorphan hydrobromide, lysergic acid diethylamide (LSD), methylenedioxymethamphetamine (ecstasy, molly), nicotine, phencyclidine (PCP)

Opioids

• Effects: pain relief, cough reduction, diarrhea relief, anesthesia induction, relaxation, and euphoria
• Heroin use can cause a brief "rush" followed by a relaxed state
• Adverse Effects: drowsiness, miosis, nausea, vomiting, respiratory depression, hypotension, constipation, and flushing
• Withdrawal Symptoms: drug seeking, mydriasis, diaphoresis, rhinorrhea, lacrimation, vomiting, diarrhea, insomnia, elevated blood pressure and pulse, intense drug desire, muscle cramps, arthralgia, anxiety, nausea, and malaise
• Opioid withdrawal peaks in 1-3 days and lasts 5-7 days
• Withdrawal Treatment: naltrexone hydrochloride, methylnaltrexone bromide, naloxone/buprenorphine hydrochloride, and methadone

Stimulants

• Effects: mood elevation, fatigue reduction, increased alertness and aggressiveness
• Stimulants affect the CNS and cardiovascular system, increasing blood pressure and heart rate
• Adverse Effects: restlessness, tremor, talkativeness, irritability, insomnia, euphoria, confusion, aggression, anxiety, delirium, paranoid hallucinations, suicidal tendencies, dry mouth, metallic taste, anorexia, nausea, vomiting, diarrhea, abdominal cramps, headache, chilliness, pallor, palpitations, tachycardia, cardiac dysrhythmias, anginal pain, hypertension or hypotension, and circulatory collapse
• Withdrawal Symptoms: social withdrawal, psychomotor retardation, hypersomnia, hyperphagia, depression, suicidal thoughts and behavior, and paranoid delusions
• Stimulant withdrawal peaks in 1-3 days and lasts 5-7 days
• Overdose: can result in convulsions, coma, or cerebral hemorrhage
• No specific pharmacological treatments are listed for stimulant withdrawal

Depressants

• Effects: relieve anxiety, irritability, and tension; treat seizure disorders and induce anesthesia
• Benzodiazepines and barbiturates increase gamma-aminobutyric acid (GABA) action in the brain, leading to sedation, muscle relaxation, and anxiety relief
• Marihuana Use Effects: mild euphoria, memory lapses, dry mouth, enhanced appetite, motor awkwardness, and a distorted sense of time and space
• Adverse Effects: drowsiness, sedation, loss of coordination, dizziness, blurred vision, headaches, nausea, vomiting, constipation, dry mouth, abdominal cramping, pruritus, and skin rash
• Withdrawal Symptoms: increased psychomotor activity, agitation, muscular weakness, hyperthermia, diaphoresis, delirium, convulsions, elevated blood pressure, pulse rate, and temperature, anxiety, depression, euphoria, incoherent thoughts, hostility, grandiosity, disorientation, hallucinations, and suicidal thoughts
• Withdrawal peaks in 2-4 days for short-acting drugs and 4-7 days for long-acting drugs
• Withdrawal lasts 4-7 days for short-acting drugs and 7-12 days for long-acting drugs
• Withdrawal Treatment: tapering of the drug over 7-14 days

Alcohol (Ethanol)

• Effects: causes CNS depression
• Adverse Effects of Chronic Ingestion: nutritional and vitamin deficiencies, Wernicke’s encephalopathy, Korsakoff’s psychosis, polyneuritis, seizures, alcoholic hepatitis (progressing to cirrhosis), cardiomyopathy, and fetal alcohol spectrum disorder (FASD)
• Withdrawal Symptoms: elevated blood pressure, pulse rate, and temperature, insomnia, tremors, and agitation
• Withdrawal Treatment: benzodiazepines (e.g., diazepam), acamprosate calcium; severe withdrawal may require monitoring in a Critical Care Unit; disulfiram, naltrexone, acamprosate calcium, and counselling for alcoholism treatment

Nicotine

• Effects: transient stimulation of autonomic ganglia, followed by depression, CNS and respiratory stimulation, increased heart rate and blood pressure, and increased bowel activity
• Withdrawal: manifested by cigarette craving, irritability, restlessness, and decreased heart rate and blood pressure
• Withdrawal Treatment: nicotine transdermal system (patch), nicotine polacrilex (gum), inhalers, nasal spray, bupropion hydrochloride, and varenicline tartrate

Nursing Implications

• Assessments should include non-judgmental questions about substance abuse
• Be observant for clues to substance misuse to avoid withdrawal symptoms
• Assessment tools include CAGE-AID, SASSI, MAST-G, and POSIT
• Patient safety is paramount during withdrawal

CNS Depressants and Stimulants

• CNS depressants reduce nervousness, excitability, and irritability
• CNS stimulants increase CNS activity
• CNS depressants can induce sleep, with the effect being dose-dependent

Categories of CNS Depressants and Specific Drugs

• Benzodiazepines: clonazepam (Rivotril®), diazepam (Valium®), flurazepam hydrochloride (Dalmane®), alprazolam (Xanax®), bromazepam (Lectopam®), lorazepam (Ativan®), temazepam (Restoril®), midazolam hydrochloride, triazolam
• Nonbenzodiazepines: zopiclone (Imovane®, Rhovane®)
• Muscle Relaxants: Baclofen (Lioresal®), cyclobenzaprine hydrochloride (Novo-Cycloprine®), dantrolene sodium (Dantrene®), tizanidine hydrochloride
• Miscellaneous Drugs: buspirone (BuSpar)

Benzodiazepines

• Mechanism of Action: depress CNS activity by affecting the hypothalamic, thalamic, and limbic systems of the brain and increasing GABA to prevent neuronal excitability
• Indications: controlling agitation and anxiety, reducing excessive sensory stimulation, inducing sleep, inducing skeletal muscle relaxation, anxiety-related depression, acute seizure disorders, alcohol withdrawal, and short-term therapy for insomnia
• Adverse Effects: mild and infrequent, including headache, drowsiness, paradoxical excitement of nervousness, dizziness, cognitive impairment, vertigo, lethargy, fall hazard for older adults, and "hangover" effect or daytime sleepiness
• Toxic Effects: somnolence, confusion, coma, and diminished reflexes; rarely results in hypotension and respiratory depression unless taken with other CNS depressants; flumazenil can be used as an antidote
• Cautions: older adult use
• Contraindications: Interactions are more likely in patients with renal or hepatic compromise
• Drug Interactions: azole antifungals, verapamil, diltiazem, protease inhibitors, macrolide antibiotics, grapefruit juice, other CNS depressants (alcohol, opioids, muscle relaxants), kava, and valerian
• Dosage forms/routes: IV or IM

Nonbenzodiazepines (zopiclone)

• Mechanism of Action: short-acting benzodiazepine-like drug
• Indications: short-term treatment of insomnia (7 to 10 days)
• Unique Advantage: very short half-life

Muscle Relaxants

• Mechanism of Action: Most are centrally acting, with the site of action in the CNS and similar structure/action to other CNS depressants; direct-acting muscle relaxants act directly on skeletal muscle and closely resemble GABA.
• Indications: relief of painful musculoskeletal conditions, muscle spasms, and management of spasticity of severe chronic disorders (multiple sclerosis, cerebral palsy)
• Adverse Effects: Extension of effects on the CNS and skeletal muscles, including euphoria, lightheadedness, dizziness, drowsiness, fatigue, confusion, and muscle weakness
• Nursing implications for muscle relaxants: Monitor for a therapeutic effect of decreased spasticity, decreased rigidity, and pain relief

Miscellaneous Anxiolytic (buspirone)

• Mechanism of Action: unknown
• Indications: reduces anxiety
• Adverse Effects: paradoxical anxiety, blurred vision, dizziness, headache, and nausea
• Cautions: may have drug interaction with SSRIs (serotonin syndrome); do not administer with MAOIs
• Unique Characteristics: nonsedating and non–habit forming; administered on a scheduled basis

Etiology and Pathophysiology of Mental Health Disorders

• The causes of mental health disorders are not fully understood
• Biochemical Imbalance Theory: disorders arise from abnormal neurotransmitter levels in the brain (dopamine, norepinephrine, serotonin, histamine, acetylcholine, and GABA) and minerals (sodium, potassium, and magnesium)
• Patients with mental health disorders may be more susceptible to various health problems like cardiometabolic syndrome; many do not seek care and may self-medicate; societal stigma remains an obstacle to treatment

Psychotherapeutic Drug Classes

• Anxiolytic drugs
• Mood-stabilizing drugs
• Antidepressant drugs
• Antipsychotic drugs
• Psychotherapeutic drugs treat emotional and mental disorders when emotions significantly affect an individual’s ability to carry out normal daily functions

Anxiolytic Drugs

• Mechanism of Action: reduce anxiety by reducing overactivity in the central nervous system (CNS)
• Types: benzodiazepines and miscellaneous drugs like buspirone
  • Benzodiazepines: depress activity in the brainstem and limbic system and increase the action of GABA
  • Buspirone: Its mechanism of action is unknown
• Indications: generalized anxiety disorder (GAD), short-term relief of anxiety symptoms, panic disorder, and anxiety associated with depression
• Therapeutic Effects: improved mental alertness, cognition, and mood, fewer anxiety and panic attacks, improved sleep patterns and appetite, less tension and irritability, fewer feelings of fear, impending doom, and stress, and more interest in self and others
• Adverse Effects: decreased CNS activity, sedation, amnesia, hypotension, drowsiness, loss of coordination, dizziness, headaches, nausea, vomiting, dry mouth, and constipation
  • Buspirone: paradoxical anxiety, blurred vision, dizziness, headache, and nausea
• Toxic Effects: dangerous when taken with other sedatives or alcohol; flumazenil may be used to reverse benzodiazepines’ effects
• Drug Interactions: alcohol, antacids, oral contraceptives; buspirone may interact with selective serotonin reuptake inhibitors (SSRIs) and should not be administered with monoamine oxidase inhibitors (MAOIs)
• Contraindications: interactions are more likely in patients with renal or hepatic compromise
• Cautions: Monitor older adult patients closely for oversedation and profound CNS depression

Antidepressant Drugs

• Mechanism of Action: increase neurotransmitter concentrations, including serotonin, dopamine, and norepinephrine
• Types: tricyclics, tetracyclics, MAOIs, SSRIs, SNRIs, and miscellaneous antidepressants
  • Tricyclic Antidepressants: block reuptake of neurotransmitters, causing accumulation at the nerve endings
  • SSRIs: increase serotonin levels in the brain by blocking the reuptake process
• Indications: major depressive disorders, anxiety disorders, eating and personality disorders, migraine, chronic pain, sleep disorders, hot flashes, and PMS
  • Tricyclic Antidepressants: neuropathic pain, insomnia, childhood enuresis, obsessive-compulsive disorders (OCDs), and sometimes anorexia
• Therapeutic Effects: improved sleep patterns and nutrition, increased feelings of self-esteem, decreased feelings of hopelessness, increased interest in self and appearance, increased interest in daily activities, and fewer depressive manifestations or suicidal thoughts or ideations
• Adverse Effects: insomnia, weight gain, and sexual dysfunction
  • Tricyclic Antidepressants: sedation, impotence, and orthostatic hypotension
• Toxic Effects: Overdose of tricyclic antidepressants is lethal, mainly affecting the CNS and cardiovascular systems
• Drug Interactions: many cautions, contraindications, and interactions exist
• Cautions: Health Canada issued a special warning about the increased potential for suicide, agitation, and behavior changes; caffeine and cigarette smoking may decrease the effectiveness of medication therapy

Mood-Stabilizing Drugs

• Mechanism of Action: treatment of bipolar disorder; lithium potentiates serotonergic neurotransmission, reduces excitatory neurotransmission (dopamine and glutamate), and increases inhibitory neurotransmission (GABA)
• Indications: treatment of bipolar disorder, effective for maintenance and acute mania
• Therapeutic Effects: less mania and therapeutic lithium levels of 0.6 to 1.2 mmol/L
• Adverse Effects: cardiac dysrhythmia, drowsiness, slurred speech, epilepsy-type seizures, choreoathetotic movements, ataxia, and hypotension; long-term treatment may cause hypothyroidism
• Toxic Effects: levels exceeding 1.5 to 2.0 mmol/L begin to produce toxicity, including gastrointestinal (GI) discomfort, tremor, confusion, somnolence, seizures, and possibly death
• Contraindications: dehydration, sodium imbalance, kidney or cardiovascular disease

Antipsychotic Drugs

• Mechanism of Action: block dopamine receptors in the brain (limbic system, basal ganglia) and decrease dopamine levels in the CNS; atypical antipsychotics also block specific serotonin receptors
• Indications: schizophrenia, drug-induced psychoses, and autism; also used to treat extreme mania, BPD, depression resistant to other therapy, certain movement disorders, and certain other medical conditions
• Therapeutic Effects: improved mood and affect, alleviation of psychotic symptoms and episodes, and decreased hallucinations, paranoia, delusions, and garbled
• Adverse Effects: agranulocytosis, hemolytic anemia, drowsiness, neuroleptic malignant syndrome (NMS), extrapyramidal symptoms (EPS), tardive dyskinesia, insulin resistance, weight gain, changes in serum lipid levels, and cardiometabolic syndrome
• Drug Interactions: avoid alcohol and other CNS depressants with these medications
• Cautions: Instruct patients to wear sunscreen because of photosensitivity and to avoid taking antacids within 1 hour of a dose; long-term haloperidol therapy may result in tremors, nausea, vomiting, or uncontrollable shaking of small muscle groups