toxic cases

Commonality and Uses of Antihistamines
- Antihistamines are commonly used and are widely available.
- They have psychoactive functions and can induce sedation as well as other unwanted effects.
Anticholinergic Effects
- Antihistamines exhibit anticholinergic properties due to their ability to block muscarinic receptors.
- Specifically, diphenhydramine has non-selective H1-receptor blocking activity.

Physical Symptoms
  - Agitation
  - Hallucinations
  - Hot, dry, flushed skin
  - Dilated pupils
  - Tachycardia (increased heart rate)
  - Hypertension (high blood pressure)
  - Urinary retention
Explanation of Symptoms
  - Tachycardia:
    - Blocking parasympathetic influence causes a rise in heart rate.
  - Dilated Pupils:
    - Results from parasympathetic blockade which prevents the constriction of pupils.
  - Dry Skin:
    - Anticholinergic effects lead to decreased sweat production due to inhibition of acetylcholine effects on sweat glands, causing an increase in local skin temperature.
  - Hypertension:
    - Blood vessels may be constricted due to increased heart rate, resulting in elevated blood pressure.
  - Flushed Skin:
    - Lack of sweating causes local vasodilation and higher temperatures, leading to flushed appearance.

Definition of Toxidrome:
- A toxidrome is a cluster of signs and symptoms indicating a specific type of poisoning or drug overdose.
Antihistamines Toxidrome:
- Typical symptoms include the aforementioned signs of anticholinergic toxicity.

Initial Assessment (ABCs):
- Assess Airway, Breathing, and Circulation (A, B, C) to prioritize patient safety.
Decontamination:
- Remove any remaining toxic substance if possible.
Additional Effects of Excess Parasympathetic Activity:
- Increased lacrimation, bronchial secretions, diarrhea, urinary incontinence, pinpoint pupils, and bradycardia can indicate potentially life-threatening toxicity.

Opiates and CNS Depression:
  - Symptoms of opioid overdose include:
    - Pinpoint pupils
    - Respiratory depression
    - Hypothermia
    - Could lead to respiratory failure.
Antidote for Opioid Overdose:
- Administer naloxone to counteract effects of opioids.

Combination of Negative Effects:
- Discuss potential interactions such as between sertraline (an antidepressant) and other medications leading to serotonin syndrome including agitation and hyporeflexia.

Acetaminophen Toxicity:
  - When overdosed, it can lead to liver damage.
  - Pathways involved in metabolism lead to N-acetyl-p-benzoquinone imine (NAPQI).
  - Treatment:
    - Use of activated charcoal and N-acetylcysteine as a detoxifying agent.

Lead Poisoning in Children:
  - Common due to ingestion of lead-containing materials.
  - Symptoms include abdominal pain, behavioral issues, and anemia due to inhibition of heme synthesis.
  - Treatment involves removing exposure and chelation therapy.
  - Why is it more common in children?
    - Children's bodies are still developing, making them more susceptible to toxicity.
    - They tend to put objects in their mouths.

Lead Contamination in History:
- Historical issues with lead in drinking water (e.g., Roman times) due to sweet-tasting lead sources.
Toxic Doses:
- Clinicians must be aware of toxic vs therapeutic doses and manage patient care accordingly.

Hypoglycemia Treatment:
- In cases of suspected intoxication with alcohol or opioids, administer dextrose to manage hypoglycemia.
Remembering Symptoms:
- Remain vigilant regarding potential combinations of substances and intoxication signs in patient evaluations while considering protective measures such as hydration and antagonist medications like naloxone for opioid toxicity.
Use of Imaging:
- If in doubt, use CT imaging for head trauma or other injuries in patients with altered mental status.