Toxicology of Stimulants, Cannabinoids, and Hallucinogens

• Psychosis
• Hyperpyrexia (extremely high body temperature)
• Tremors and Seizures
• Cardiac Arrest

Clinical Management Tip: When managing a stimulant overdose, your priorities are to establish and maintain the airway, maximize oxygen saturation, prevent seizures through adequate sedation, and continuously monitor serial vital signs.

Cannabinoids

Cannabinoids are derived from the Cannabis sativa plant. The end product of the harvested and dried leaves is commonly known as marijuana.

Delta-9-Tetrahydrocannabinol (THC)

The primary psychoactive component in cannabis is delta-9-tetrahydrocannabinol (THC). While cannabinoids are sometimes classified as hallucinogens, they typically do not produce "true" hallucinations. Instead, they cause a distorted sense of time and space, as well as a general feeling of unreality.

Clinical Presentation

Common signs and symptoms of marijuana use include:

• Euphoria and drowsiness
• Decreased short-term memory and diminished motor coordination
• Increased appetite
• Injected conjunctiva (red eyes)
• Physiological effects such as bronchodilation and slight tachycardia

Management

The likelihood of serious medical complications from cannabis is small. Management is primarily supportive prehospital care, and transport to a hospital is rarely warranted unless other substances are involved.

Hallucinogens

Hallucinogens are substances that cause significant distortions in sensory perception, often referred to as "psychedelic effects". These experiences can vary markedly between individuals.

LSD (Lysergic Acid Diethylamide)

LSD primarily affects the senses and is known for causing synesthesias, a phenomenon where the senses "cross" (e.g., seeing sounds or hearing colors). The physiological effects of LSD are largely sympathomimetic.

Dissociative Anesthetics: PCP and Ketamine

Dissociative anesthetics are a specific class of hallucinogens that cause a sense of mind-body separation.

• Phencyclidine (PCP): Originally developed in the late 1950s, PCP is now primarily used as an animal tranquilizer. In humans, it is often smoked or snorted and is associated with violent outbursts, bizarre comments, and an "unfathomable" ability to withstand pain or exhibit near-superhuman strength.
• Ketamine: A PCP analogue, ketamine is a colorless, odorless powder that is often mixed into drinks. It is both physically and psychologically addictive.

Psilocybin Mushrooms

Psilocybin mushrooms are naturally occurring hallucinogens. While they can cause significant sensory distortions, the likelihood of serious side effects is low, and prehospital treatment remains primarily supportive.

Summary of Management Strategies

Regardless of the specific psychoactive agent, the foundational approach to toxicological emergencies remains consistent:

1. Scene Safety: Ensure the scene is safe for access and egress, especially with potentially violent patients (e.g., PCP).
2. Airway and Breathing: Establish and maintain a patent airway and ensure adequate ventilation.
3. Circulation: Establish vascular access and be prepared to manage shock, arrhythmias, or cardiac arrest.
4. Supportive Care: Administer high-concentration supplemental oxygen and monitor vital signs continuously.