Toxicology
Substance Use Disorders
| Mechanism | Medication | Indications |
|---|---|---|
| Adenosine antagonists | Caffeine | Stimulant |
| NN [Ganglionic] agonists | Nicotine | Stimulant |
| NDRI | Cocaine | Stimulant |
| Amphetamine MDMA [Ecstasy] | Stimulant Hallucinogen | |
| 5-HT2 agonists | Lysergic acid diethylamide (LSD) | Hallucinogen |
| NMDA antagonists | Ketamine Phencyclidine (PCP) [Angel dust] | Hallucinogen |
| Cannabinoid agonists | Cannabis [Marijuana] | Hallucinogen |
| - | Psilocybin | Hallucinogen |
| GABAA agonists | Alcohol | Depressant |
| GABAB agonists | γ-Hydroxybutyrate (GHB) | Depressant |
| μ-opioid agonists | Heroin | Depressant |
Treatment of Substance Use Disorders
| Subtance | Toxicity | Withdrawal | Cessation |
|---|---|---|---|
| Nicotine | - | - | Nicotine Varenicline Bupropion |
| Cocaine | Benzodiazepines | - | - |
| Phencyclidine (PCP) | Benzodiazepines | - | - |
| Benzodiazepines | Flumazenil | Benzodiazepines | - |
| Alcohol | - | Benzodiazepines | Disulfiram Naltrexone |
| Opioids | Naloxone | Opioids Clonidine Guanfacine | Methadone Buprenorphine |
Antidotes for Toxins
| Toxin | Antidotes |
|---|---|
| Acetaminophen | N-acetylcysteine |
| Anticholinesterases Organophosphates | Atropine Pralidoxime |
| Anticholinergics | Physostigmine |
| Botulism | Antitoxin |
| β antagonists | Glucagon |
| Ca channel blockers | Calcium |
| Cocaine | Benzodiazepines |
| Phencyclidine (PCP) | Benzodiazepines |
| Barbiturates | NaHCO3 |
| Benzodiazepines | Flumazenil |
| Methanol Propylene glycol Ethylene glycol | Fomepizole Ethanol |
| Opioids | Naloxone |
| Valproate | L-carnitine |
| Salicylate TCAs | NaHCO3 |
| Sulfonylureas | Octreotide |
| Digitalis | Anti-digitalis K & Mg |
| Warfarin | FFP / PCC Vitamin K |
| Heparin | Protamine sulfate |
| Factor 10a inhibitors | FFP / PCC Andexanet alfa |
| tPAs | Cryoprecipitate Antifibrinolytics |
| Arsenic [As] Mercury [Hg] Gold [Au] | Succimer Dimercaprol |
| Iron [Fe] | Deferasirox Deferoxamine Deferiprone |
| Copper [Cu] | Penicillamin Trientine |
| Lead [Pb] | Succimer Dimercaprol EDTA |
| Lithium [Li] | Hemodialysis |
| Carbon monoxide [CO] | 100% O2 Hyperbaric O2 |
| Cyanide | Hydroxocobalamin Thiosulfate Nitrites |
| Methemoglobin | Methylene blue Vitamin C |
Comparison Between CO Poisoning and Methemoglobinemia
| Disorder | SpO2 | SaO2 | PaO2 |
|---|---|---|---|
| CO Poisoning | - | ↓ | - |
| Methemoglobinemia | ↓ | ↓ | - |
Presentation of Lead Poisoning {LEAD}
- Lead [Burton] line
- Encephalopathy
- Erythrocyte basophilic stippling
- Abdominal colic
- Anemia :: sideroblastic anemia
- Drops :: wrist & foot drop
Management of Lead Poisoning
| Level (μg/dL) | Management |
|---|---|
| 5 ~ 45 | Observation |
| 45 ~ 70 | Succimer |
| > 70 | Dimercaprol EDTA |
CAGE Questions for Alcohol Use {CAGE}
- Cut down
- Anger
- Guilty
- Eye-opener
Clinical Effects of Blood Alcohol Concentration (BAC)
| BAC (mg/dL) | Effects |
|---|---|
| 20 ~ 50 | ↓ Fine motor coordination |
| 50 ~ 100 | ↓ Judgment ↓ Coordination |
| 100 ~ 150 | Gait disturbance |
| 150 ~ 250 | Lethargy |
| 300 | Coma |
| 400 | Respiratory depression |
Timeline of Alcohol Withdrawal Symptoms
- Tremors
- Hallucinosis
- Seizure & Sleep deprivation
- Delirium tremens
Presentation of Fetal Alcohol Syndrome (FAS)
- Intrauterine growth retardation (IUGR)
- Short palpebral fissure
- Midfacial hypoplasia
- Smooth philtum
- Thin vermilion border
- Microcephaly
- Mental retardation
Presentation of Digitalis Toxicity
- Hyperkalemia
- Blurry vision
- Yellow halos
- Bradycardia
- ECG changes
- AV blocks
- Scooped ST segment
- Bidirectional VT
- GI symptoms