Immex (Loperamide Hydrochloride)

Loperamide Hydrochloride is an antidiarrheal that acts on intestinal motility to manage various diarrheal conditions.

• Acute nonspecific diarrhea: reduces stool frequency and improves stool consistency.
• Chronic diarrhea associated with inflammatory bowel disease: helps control symptoms by slowing transit.
• Travelers' diarrhea: provides symptomatic relief during short‑term travel‑related episodes.

• Loperamide Hydrochloride binds to μ‑opioid receptors in the myenteric plexus of the gastrointestinal tract. This agonist activity decreases the release of acetylcholine and other excitatory neurotransmitters, leading to reduced smooth‑muscle contractions and slower intestinal transit. The prolonged contact time allows increased absorption of water and electrolytes, resulting in firmer stools and decreased frequency of bowel movements. It does not significantly cross the blood‑brain barrier, limiting central opioid effects.

Loperamide Hydrochloride may cause a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Constipation: reduced bowel movements leading to hard stools.
• Abdominal cramping: mild to moderate discomfort in the abdomen.
• Nausea: feeling of queasiness.
• Dizziness: light‑headed sensation.
• Dry mouth: reduced salivation.
• Drowsiness: mild sedation.

Serious or Rare Side Effects

• Severe constipation or intestinal obstruction: risk of blockage requiring medical attention.
• Toxic megacolon: rare but life‑threatening colonic dilation.
• Allergic reactions: rash, urticaria, or angioedema.
• Cardiac arrhythmias: QT prolongation leading to irregular heartbeat.

When using Loperamide Hydrochloride, several precautions should be observed to ensure safe and effective therapy.

• Indication limitation: use only for short‑term relief of non‑infectious diarrhea.
• Infectious diarrhea avoidance: do not use if diarrhea is caused by bacteria, parasites, or toxins.
• Hepatic impairment caution: dose may need adjustment in patients with liver disease.
• Drug‑interaction awareness: avoid concurrent use with other antidiarrheals or opioid agonists.
• Allergic reaction monitoring: discontinue if rash, swelling, or breathing difficulty occurs.
• Store at room temperature: keep in the original packaging, protect from moisture and direct sunlight.

Loperamide Hydrochloride can interact with other medicines, affecting its efficacy or safety.

Major Interactions (Avoid)

• Other antidiarrheal agents (e.g., diphenoxylate): combined effect may cause severe constipation.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): increase plasma levels and risk of cardiac toxicity.
• Opioid analgesics (e.g., morphine): additive central opioid effects may lead to respiratory depression.

Moderate Interactions (Monitor Closely)

• CYP3A4 inducers (e.g., rifampin, carbamazepine): may reduce effectiveness.
• Anticholinergic drugs (e.g., diphenhydramine): may enhance dry mouth and constipation.
• QT‑prolonging agents (e.g., macrolide antibiotics): monitor cardiac rhythm.