Cinaron Plus

Approved Indications:

• Vertigo and Vestibular Disorders:
  Symptomatic treatment of vertigo, dizziness, nausea, tinnitus, and balance disturbances associated with:
• Ménière’s disease
• Labyrinthitis
• Vestibular neuritis
• Benign paroxysmal positional vertigo (BPPV)
• Other peripheral vestibular disorders
• Motion Sickness:
  Prevention and management of motion-related nausea and vomiting.

Off-label/Clinically Accepted Uses:

• Adjunctive treatment in:
• Vestibular migraine
• Acute vertigo in inner ear ischemia or post-traumatic labyrinthine disorders
• Non-vestibular dizziness of uncertain origin (with caution)

Adults:

• Standard Dose:
  1 tablet (Cinnarizine 20 mg + Dimenhydrinate 40 mg) three times daily (TID).
• Maximum Dose:
  Up to 5 tablets/day may be used in severe cases under medical supervision.

Pediatrics:

• Not recommended in children under 12 years.
• Adolescents (≥12 years): Same dose as adults, only under physician guidance.

Elderly:

• Start with lower doses (e.g., 1 tablet twice daily) and adjust based on tolerability.
• Monitor for sedation and anticholinergic effects.

Hepatic/Renal Impairment:

• Use with caution; no specific dose adjustment required but monitor for adverse effects due to reduced metabolism or clearance.

Administration Route:
Oral. Tablets should be swallowed whole with water, preferably after meals to reduce gastric irritation.

This combination acts synergistically to control vertigo and nausea.

• Cinnarizine selectively blocks L-type and T-type calcium channels in vascular smooth muscles, promoting vasodilation and improving blood flow in the vestibular and cerebral regions. It also has antihistaminic (H1-blocking) activity that suppresses vestibular stimulation, reducing motion-induced symptoms.
• Dimenhydrinate is a first-generation H1-antihistamine composed of diphenhydramine and 8-chlorotheophylline. It stabilizes vestibular input to the vomiting center and chemoreceptor trigger zone (CTZ), mitigating nausea, vomiting, and vertigo. Its sedative and antiemetic effects further enhance symptom control.
  Together, these agents reduce vestibular hyperexcitability and improve balance regulation in inner ear disorders.

• Absorption:
  Rapidly absorbed from the gastrointestinal tract.
  Onset of action typically within 30–60 minutes.
• Bioavailability:
  Moderate for both components due to first-pass metabolism.
• Distribution:
  Both drugs cross the blood-brain barrier and distribute to CNS tissues.
• Metabolism:
• Cinnarizine: Hepatically metabolized via CYP2D6.
• Dimenhydrinate: Rapidly hydrolyzed to diphenhydramine (active) and metabolized in the liver.
• Half-life:
• Cinnarizine: ~3–6 hours
• Diphenhydramine (from dimenhydrinate): ~4–8 hours
• Elimination:
  Mainly excreted in the urine as metabolites; some fecal excretion.

• Pregnancy:
  Not assigned a formal FDA category. Use only if clearly indicated.
  Animal data have not shown major teratogenicity, but human data are limited.
• Lactation:
  Both agents may be excreted into breast milk.
  Use is not recommended during breastfeeding due to possible CNS effects (e.g., sedation, irritability) in infants.

• Therapeutic Class:
  Antivertigo combination
• Pharmacologic Class:
• Cinnarizine: Calcium channel blocker and antihistamine
• Dimenhydrinate: Antihistamine (H1) and antiemetic (first-generation)

• Known hypersensitivity to cinnarizine, dimenhydrinate, or diphenhydramine
• Parkinson’s disease (risk of worsening extrapyramidal symptoms)
• Epilepsy (may lower seizure threshold)
• Angle-closure glaucoma
• Urinary retention or prostatic hypertrophy
• Severe hepatic dysfunction
• Children under 12 years

• Sedation: May impair mental alertness; avoid driving or machinery use.
• Extrapyramidal Effects: Risk increases with prolonged use or in elderly.
• CNS Depression: Additive effects with alcohol or other sedatives.
• Anticholinergic Effects: Use cautiously in asthma, glaucoma, and urinary retention.
• Hepatic Impairment: Monitor closely due to hepatic metabolism.
• Long-term Use: Not advised; should be limited to acute management.

Common:

• Drowsiness
• Dry mouth
• Headache
• Gastrointestinal discomfort
• Sedation or fatigue

Less Common:

• Weight gain (with prolonged use)
• Orthostatic hypotension
• Photosensitivity

Rare/Serious:

• Extrapyramidal symptoms (rigidity, tremors, bradykinesia)
• Allergic reactions (rash, pruritus, urticaria)
• Hepatic dysfunction
• Hallucinations or confusion (especially in elderly)

Timing:
Most side effects begin within 1–3 hours of dosing; extrapyramidal signs appear with chronic use.

• CNS Depressants (e.g., alcohol, benzodiazepines, opioids): Enhanced sedation
• Anticholinergics (e.g., atropine, tricyclics): Increased risk of dry mouth, constipation, and urinary retention
• Levodopa: Antagonism of antiparkinsonian effect
• CYP2D6 Inhibitors (e.g., fluoxetine, paroxetine): May alter cinnarizine metabolism
• Monoamine Oxidase Inhibitors (MAOIs): Potentiation of antihistamine toxicity

• Combination recognized in European vertigo management protocols as effective for acute peripheral vertigo.
• Caution advised by some clinical guidelines for long-term use due to Parkinsonism risk, especially in elderly.
• No recent regulatory changes in dosing or contraindications.

• Temperature: Store below 25°C (77°F)
• Humidity: Keep in a dry place, protected from moisture
• Light Protection: Store in original packaging, away from direct sunlight
• Handling: Keep out of reach of children; do not use if expired
• Reconstitution/Refrigeration: Not applicable