Paramedic: Paramedic Medications 4 Neurologic and GI
This advanced pharmacology lesson focuses on neurological and gastrointestinal (GI) medications relevant to paramedic practice. These classes of medications often address critical patient complaints related to pain, altered mental status, and digestive emergencies. Understanding their mechanisms of action, indications, contraindications, and side effects is crucial for safe and effective patient management at the paramedic level.
Neurologic Medications: Managing Pain and Altered Mental Status
Neurologic medications primarily impact the Central Nervous System (CNS) and are often used for pain management or to address altered mental status.
Opioid Medications (Narcotics)
Opioids are potent analgesics that stimulate opioid receptors in the brain to relieve pain. They are effective but carry significant risks, including tolerance, cross-tolerance, and addiction.
Effects: Analgesia, euphoria, sedation, respiratory depression, constipation.
Commonly Used in EMS:
Morphine Sulfate: A naturally occurring opiate, known for causing nausea and histamine release. Often given with anti-emetics.
Fentanyl (Sublimaze): A synthetic opioid, generally associated with less nausea and histamine release than morphine. Can be administered intranasally.
Key Considerations: Profound sedation and respiratory depression are critical concerns. Naloxone (Narcan) is the reversal agent for opioid overdose, but its duration of action may be shorter than the opioid.
Gastrointestinal Medications: Addressing Digestive Distress
GI medications are used to manage various conditions affecting the gastrointestinal tract, from nausea and vomiting to acid reflux.
Antiemetics
These medications are used to prevent or reduce nausea and vomiting.
Commonly Used in EMS:
Ondansetron (Zofran): A serotonin 5-HT3 receptor antagonist, very effective for various causes of nausea and vomiting. Can be given IV or ODT (oral dissolving tablet).
Promethazine (Phenergan): An antihistamine with antiemetic, sedative, and anticholinergic effects. Often administered cautiously due to potential for sedation and extrapyramidal symptoms.
Key Considerations: Assess for dehydration and electrolyte imbalances associated with persistent vomiting. Choose routes of administration carefully, especially with altered mental status.
Antacids/H2 Blockers/Proton Pump Inhibitors (PPIs)
While less commonly administered acutely in the prehospital setting, paramedics should be aware of these medications as patients often take them for chronic GI issues like GERD or peptic ulcer disease.
Antacids: Neutralize stomach acid (e.g., calcium carbonate).
H2 Blockers: Reduce acid production (e.g., ranitidine).
PPIs: Potently suppress acid production (e.g., omeprazole).
Understanding a patient's home medication list, including these, can help rule out less critical GI complaints versus life-threatening conditions.
Other Relevant GI Considerations
Laxatives/Antidiarrheals: Patients may be taking these, and their use or lack thereof can provide clues to underlying conditions (e.g., severe constipation, infectious diarrhea).
GI Bleeds: While medications may not be administered directly, recognizing the signs and symptoms of upper or lower GI bleeds (e.g., hematemesis, melena, hematochezia) is crucial. Management focuses on airway protection, circulatory support, and rapid transport.
Key Pharmacological Principles
When administering any medication, paramedics must adhere to the "Six Rights of Medication Administration" and consider:
Mechanism of Action: How the drug produces its effects.
Indications: The specific conditions for which the drug is approved.
Contraindications: Conditions where the drug should not be given.
Side Effects: Unintended but often predictable effects.
Dosage and Route: Correct amount and method of administration.
Drug Interactions: Potential effects when given with other medications.
Critical Thinking Questions
A patient with severe abdominal pain is prescribed morphine. What are the key considerations for administering this medication in the prehospital setting, and what side effects would you closely monitor for?
You encounter a patient who is unconscious with pinpoint pupils and shallow respirations. Their friend states they "took too much of their pain pills." What is your suspected toxidrome, and what immediate pharmacological intervention is indicated?
A patient with nausea and vomiting is given Ondansetron. What is the mechanism of action of this drug, and how does it differ from a drug like Promethazine?
Discuss the importance of obtaining a thorough medication history (including over-the-counter and herbal remedies) for a patient with a GI complaint, even if you do not plan to administer GI medications yourself.
You are treating a patient with signs of a significant upper GI bleed. While you won't be administering medications to stop the bleeding, what are your immediate management priorities, and how do they relate to the patient's neurological and circulatory status?