Pharmacology Notes: Anticholinergics and Steroids

Anticholinergics

  • Inhibit acetylcholine in the Peripheral Nervous System (PNS).
  • Effectively inhibits the PNS, which is responsible for "rest and digest" functions.
  • PNS controls bodily functions such as digestion and urination.
  • Mnemonic for anticholinergic effects: "Can't pee, can't see, can't spit, can't sh*t."
  • Adverse effects include:
    • Urinary retention: Monitor intake and output (I&O).
    • Blurred vision: Educate patients about blurry vision, suggest wearing sunglasses, and using lubricating eye drops.
    • Dry mouth: Recommend sugar-free candy/gum or mouth moisturizer; increase fluid intake.
    • Constipation: Increase fluid and fiber intake and promote movement.
  • Opioids have anticholinergic effects, leading to constipation and urinary retention.
  • Contraindications:
    • BPH (Benign Prostatic Hyperplasia) due to the risk of urinary retention.
    • Glaucoma due to increased intraocular pressure affecting the optic nerve.
  • Acute conditions to avoid anticholinergics:
    • Urinary retention.
    • Bowel obstruction.

Opioids and Addiction Treatment

  • Medication-Assisted Treatment (MAT) involves using medications to help individuals with opioid addiction and reduce withdrawal symptoms.
  • Medications used include naltrexone, Suboxone, and methadone.
  • Adjuvant therapy involves using medications from different drug classes for pain management (e.g., gabapentin or pregabalin for neuropathic pain).
  • Patient-Controlled Analgesia (PCA) pumps:
    • Contain morphine or hydromorphone (Dilaudid).
    • Only the patient should press the button.
    • Monitor vital signs and respiratory rate.
    • The machine shuts off if respiratory rate drops too low.

Steven Johnson Syndrome

  • Begins with flu-like symptoms (malaise, body aches, fever).
  • Progresses to blisters on mucous membranes.
  • Skin sloughs off as the condition runs its course.
  • Lamotrigine (Lamictal) is a medication strongly associated with Stevens Johnson syndrome.
    • It's used for seizures and as a mood stabilizer.

Migraines

  • Medications:
    • Ergot alkaloids.
    • NSAIDs (decrease inflammation).
    • Triptans (e.g., sumatriptan): vasoconstrictors, taken at the onset of a migraine; can be taken again two hours later.
  • Triptans come in various forms due to nausea and vomiting associated with migraines.
  • Associated symptoms: auras, photophobia, phonophobia.
  • Preventative medication: beta blockers (e.g., metoprolol).

Steroids

  • Steroids include inhaled, topical, oral, and intravenous forms.
  • Steroids end in "-one" or "-olone" (e.g., prednisone, prednisolone, methylprednisolone).
  • Cause hyperglycemia (elevated blood sugar).
    • Monitor for polydipsia, polyuria, and polyphagia (the three "polys").
  • Tapering is necessary to prevent adrenocorticoid insufficiency.
    • Steroids suppress the adrenal gland; tapering allows it to recover.
    • Never stop steroids abruptly.
  • Adverse effects:
    • Weight gain.
    • Hypernatremia.
    • Cushing's syndrome (with prolonged use): abdominal growth, striae, smaller arms and legs, excessive hair (hirsutism), moon face, humpback.
    • Osteoporosis due to hypocalcemia.
    • GI upset; take with food.
    • Increased risk of GI bleed; monitor for GI bleeding.
    • Contraindicated in patients with peptic ulcer disease.
    • Increased infection risk: protective environment needed (no live vaccines, wear a mask, avoid fresh fruits/vegetables/flowers, bathe daily with antibacterial soap).
    • Can cause bizarre behavior, euphoria, and hypertension.
  • Mechanism: suppress airway mucus, immune response, and adrenal function to decrease inflammation.
  • Forms: oral, inhaled, IV, topical.
    • Topical: can thin skin.
    • Inhaled: can cause thrush; rinse mouth after use.
  • Can cause hypokalemia.
  • Considerations:
    • Patients under stress may need a higher dose.
    • Avoid NSAIDs.
    • Fluid retention can occur.
  • Cushing's syndrome has an antidote: ketoconazole.