Iremia (Fentanyl Citrate)

Fentanyl citrate is an opioid analgesic used primarily in the management of severe pain.

• Cancer breakthrough pain: provides rapid relief of episodic pain in patients already receiving opioid therapy.
• Chronic cancer pain: contributes to sustained analgesia when other opioids are insufficient.
• Severe postoperative pain: used for short‑term control of intense pain after surgery in opioid‑tolerant individuals.

• Fentanyl citrate acts as a potent μ‑opioid receptor agonist. By binding to these receptors in the central nervous system, it inhibits the transmission of nociceptive signals and alters the perception of pain, producing strong analgesic effects while also influencing respiratory and gastrointestinal pathways.

Fentanyl citrate may cause a range of adverse reactions.

Common Side Effects

• Nausea: feeling of sickness or urge to vomit.
• Constipation: reduced bowel movements and hard stools.
• Drowsiness: increased sleepiness or fatigue.
• Dizziness: sensation of light‑headedness or unsteadiness.
• Dry mouth: reduced salivation leading to a parched feeling.
• Vomiting: expulsion of stomach contents.

Serious or Rare Side Effects

• Respiratory depression: slowed or shallow breathing that can be life‑threatening.
• Severe hypotension: marked drop in blood pressure.
• Cardiac arrest: sudden loss of heart function.
• Adrenal insufficiency: inadequate production of adrenal hormones.
• Seizures: uncontrolled electrical activity in the brain.
• Anaphylaxis: severe allergic reaction with swelling, rash, and difficulty breathing.

When prescribing or dispensing fentanyl citrate, careful consideration of patient safety is essential.

• Assess opioid tolerance: confirm the patient is opioid‑tolerant before initiating therapy.
• Monitor respiratory function: observe for signs of slowed breathing, especially after dose changes.
• Avoid concurrent CNS depressants: limit use with benzodiazepines, alcohol, or other sedatives.
• Use the lowest effective dose: titrate to achieve pain control while minimizing risk.
• Educate on dependence risk: inform patients about the potential for addiction and proper disposal.
• Store at ambient temperature: keep in the original container, protect from moisture and direct sunlight.

Fentanyl citrate can interact with other medicines, altering its safety or effectiveness.

Major Interactions (Avoid)

• Benzodiazepines or other CNS depressants: may cause profound respiratory depression.
• Monoamine oxidase inhibitors (MAOIs): increase risk of severe hypotension and serotonin syndrome.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, erythromycin): raise fentanyl plasma levels, heightening toxicity.

Moderate Interactions (Monitor Closely):\n- CYP3A4 inducers (e.g., rifampin, carbamazepine): may reduce analgesic effect.

• Serotonergic agents (e.g., SSRIs, tramadol): monitor for serotonin syndrome symptoms.