Substance Use Disorders 1

Drug Abuse: Using a drug in a way that is inconsistent with medical or social norms.
Drug Addiction: A disease characterized by the continued use of specific psychoactive substances despite causing physical, psychological, or social harm.
Substance Use Disorder (SUD):
- Similar to addiction but focuses on behavior.
- Persistent use accompanied by behaviors indicative of abuse.
Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5): Defines SUD as:
- Continued use despite significant related problems.
- Changes in brain circuitry that persist even after detoxification.
Diagnosis is based on ongoing behaviors related to substance use.

Tolerance:
- Not always an indicator of addiction.
Cross-tolerance:
- A situation where tolerance to one drug leads to tolerance of another.
Psychological Dependence:
- Characterized by intense cravings.
Physical Dependence:
- Contributes to addiction behavior; however, it is not the sole cause.
- Abstinence syndrome may occur upon withdrawal.
Cross-dependence:
- One drug can mitigate withdrawal symptoms of another.
Withdrawal Syndrome:
- Symptoms that occur after the cessation of a drug.

Transition from voluntary to compulsive drug use due to molecular changes in the brain with repeated exposure.
Reward Circuit:
- Activated circuits reinforce survival behaviors.
- Major neurotransmitter involved is dopamine.
- Addictive substances result in a stronger dopamine release compared to natural rewards.

With appropriate therapy, 40-60% of individuals can reduce drug usage.
Ideal Treatment Goals:
- Complete cessation of drug use.
- Changing compulsive drug use to moderate use is beneficial.
Challenges:
- Sustained moderation is particularly difficult for alcohol, opioid, and cigarette users.

Patient expresses that current oxycodone dosage is no longer effective, suggesting development of:
- A: Physical dependence
- B: Tolerance (Correct answer)
- C: Withdrawal syndrome
- D: An addiction

Nicotine and Tobacco Use Disorder (TUD):
- Most common substance use disorder encounter.
- Predominant form of tobacco use in the U.S. is smoking.
- Other forms: Chewing tobacco, e-cigarettes.
- Cigarette smoking is the leading preventable cause of illness and premature death.

Physiological Effects:
- Increases heart rate, blood pressure, and gastrointestinal motility.
- Can cause diarrhea, increased stomach acid leading to gastric reflux, and reduced appetite.

Cardiovascular Effects:
- Constricts blood vessels, increases heart rate and ventricular contraction strength, leading to higher blood pressure.
Gastrointestinal Effects:
- Boosts gastric acid secretion and gastrointestinal tone and motility; can induce vomiting.

Effects on CNS:
- Stimulates respiration and affects EEG patterns; can cause tremors and convulsions at high doses.
- Increases alertness, memory, cognition, and suppresses appetite.
- Activates the reward circuit, similar to other drugs like cocaine.
Pregnancy & Lactation Risks:
- Nicotine is harmful to fetuses and is also present in breast milk.

Consequences of Nicotine Use:
- Development of tolerance and dependence; risk of acute poisoning.
Treatment:
- Reducing nicotine absorption and supporting respiration, including activated charcoal and ventilatory support.

Smoked Tobacco:
- Most dangerous method; harms nearly all body organs; linked to numerous conditions in the U.S.
Smokeless Tobacco:
- Lesser risk of lung disease but poses risks for periodontal diseases and various types of cancer.

5 A's Framework:
1. Ask: Screen for tobacco use.
2. Advise: Recommend quitting.
3. Assess: Determine willingness to quit.
4. Assist: Provide medications and counseling referrals.
5. Arrange: Schedule follow-ups within the first week of quitting.

Nicotine Replacement Products:
- Available over-the-counter (OTC): patches, lozenges, gum.
- Prescription options: inhalers and nasal sprays.
Non-Nicotine Medications:
- Varenicline and Bupropion.

Effectiveness:
- Doubles chances of cessation.
Adverse Effects:
- Soreness, jaw ache, belching, and hiccups.
Usage Tip:
- Chew slowly for about 30 minutes, avoiding food/drink for 15 minutes pre- and during chewing.

Effectiveness:
- Doubles cessation success rate.
Adverse Effects:
- Mouth irritation, dyspepsia, and nausea.
Usage Tip:
- Allow to dissolve over 20-30 minutes, avoiding food/drink during this time.

Effectiveness:
- Doubles chances of cessation success.
Adverse Effects:
- Erythema, itching, and burning under the patch.
Application Instructions:
- Apply once daily, rotate site, and avoid reuse for a week.

Effectiveness:
- Doubles cessation success rate.
Adverse Effects:
- Dyspepsia, throat irritation, and oral burning.
Usage Instructions:
- Frequent puffs over 20 minutes; not suitable for asthma patients.

Effectiveness:
- Doubles cessation success rate.
Adverse Effects:
- Rhinitis, sneezing, watering eyes, nasal, and throat irritation.
Effect on Nicotine Levels:
- Rapid increase in nicotine levels; mimics pleasurable effects of cigarettes.

Functionality:
- An atypical antidepressant that helps reduce smoking urges and alleviates withdrawal symptoms.
Adverse Effects:
- Dry mouth and insomnia.

Functionality:
- Acts as a partial agonist at nicotinic receptors; most effective smoking cessation aid.
- Atypical antidepressant category.
Adverse Effects:
- Nausea, sleep disturbances, headaches, neuropsychological effects, and cardiovascular risks.
- Not recommended for certain job roles (e.g., drivers, pilots).

Products like naltrexone, silver acetate, beta blockers, benzodiazepines, and various antidepressants other than bupropion SR and nortriptyline.
Electronic cigarettes (e-cigarettes) are also discouraged.

Teaching Points for Patients:
- A: The reduction of nicotine can decrease blood pressure.
- B: Cannot assure weight loss from nicotine reduction.
- C: Misleading; smoking typically increases heart rate and decreases respiratory rate.
- D: Incorrect; smoking increases heart workload.