Navidoxine (Meclozine Hydrochloride)

Navidoxine (meclozine hydrochloride) is an antihistamine used to manage vestibular‑related nausea and related conditions.

• Motion sickness: Reduces nausea and vomiting associated with travel by sea, air, or land.
• Vertigo: Alleviates dizziness and associated nausea caused by inner‑ear disturbances.
• Nausea and vomiting: Controls acute episodes of nausea and vomiting unrelated to gastrointestinal disease.

• Meclozine hydrochloride acts as an antagonist at peripheral histamine H1 receptors, blocking the action of histamine released during vestibular stimulation. By inhibiting these receptors, it reduces the neural signals that trigger the vomiting centre in the brainstem, thereby diminishing nausea and vomiting associated with motion and vestibular disorders.

Adverse reactions may occur with any medication and should be monitored.

Common Side Effects

• Drowsiness: May cause mild to moderate sedation.
• Dry mouth: Reduced salivary secretion leading to a dry sensation.
• Blurred vision: Temporary visual disturbances.
• Constipation: Slowed gastrointestinal motility.
• Headache: Mild to moderate head pain.
• Nausea: Occasionally paradoxical.

Serious or Rare Side Effects

• Allergic reactions: Rash, itching, swelling, or difficulty breathing.
• Cardiac arrhythmia: Rare irregular heartbeats.
• Severe drowsiness: Excessive sedation that impairs daily activities.
• Acute glaucoma: Sudden increase in intra‑ocular pressure.
• Hemolytic anemia: Very rare blood disorder.

Before using Navidoxine, consider the following safety measures.

• Avoid operating machinery: Drowsiness may impair coordination and reaction time.
• Caution with alcohol: Combined use can enhance sedation.
• Use in the elderly: Increased sensitivity to anticholinergic effects.
• Monitor for allergic reactions: Discontinue if rash or swelling develops.
• Pregnancy and lactation: Consult a healthcare professional before use.
• Store at ambient temperature: Keep below 25°C in the original packaging, protected from moisture.

Navidoxine may interact with other substances; review the following categories.

Major Interactions (Avoid)

• Alcohol: Potentiates central nervous system depression.
• Other sedating antihistamines: Increases risk of excessive drowsiness.
• Monoamine oxidase inhibitors (MAOIs): May amplify anticholinergic effects.

Moderate Interactions (Monitor Closely)

• CNS depressants (e.g., benzodiazepines): Observe for enhanced sedation.
• Anticholinergic drugs (e.g., atropine): May worsen dry mouth and constipation.
• CYP450 inhibitors: Potentially increase meclozine plasma levels.