Mezolar Matrix (Fentanyl)

Fentanyl, an opioid analgesic, is used for managing severe pain that requires continuous opioid delivery.

• Chronic cancer pain: provides sustained analgesia for patients with malignant disease requiring long‑term opioid therapy.
• Severe chronic non‑cancer pain: offers round‑the‑clock pain control when other treatments are insufficient.
• Palliative/end‑of‑life care: relieves refractory pain in patients receiving hospice or terminal care.

• Fentanyl binds with high affinity to mu‑opioid receptors in the central nervous system, activating inhibitory G‑protein pathways that reduce neuronal excitability, diminish pain signal transmission, and produce analgesia and sedation. The transdermal system releases fentanyl steadily into systemic circulation, maintaining plasma concentrations within the therapeutic window for extended periods.

Fentanyl may cause a range of adverse reactions, from mild to life‑threatening.

Common Side Effects

• Nausea: mild to moderate upset stomach.
• Constipation: reduced bowel motility.
• Somnolence: increased sleepiness.
• Dizziness: feeling light‑headed.
• Dry mouth: reduced salivation.
• Application site reaction: erythema or itching at the patch site.

Serious or Rare Side Effects

• Respiratory depression: slowed or shallow breathing.
• Severe hypotension: marked drop in blood pressure.
• Adrenal insufficiency: cortisol deficiency.
• Skin necrosis: tissue death at the patch site.
• Anaphylaxis: severe allergic reaction.
• Opioid dependence or abuse: risk of addiction with prolonged use.

When prescribing or dispensing Mezolar Matrix, consider the following safety measures.

• Assess opioid tolerance: confirm patient has prior opioid exposure before initiating therapy.
• Evaluate respiratory function: monitor for existing respiratory compromise.
• Monitor for sedation: watch for excessive drowsiness or impaired cognition.
• Avoid concomitant CNS depressants: limit use with benzodiazepines or alcohol.
• Use the lowest effective dose: titrate to achieve pain control with minimal side effects.
• Store at room temperature: keep patch in original foil, protect from moisture and direct light.

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

Major Interactions (Avoid)

• CNS depressants (e.g., benzodiazepines, barbiturates): may cause profound respiratory depression.
• MAO inhibitors: increase risk of severe hypotension and serotonin syndrome.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): raise fentanyl plasma levels.

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

• Serotonergic agents (e.g., SSRIs, SNRIs): risk of serotonin syndrome.
• Alcohol: can enhance sedative effects and respiratory depression.