Drug Class: First-Generation Antihistamine | Antiemetic | Vestibular Suppressant | Form: Oral Tablet | Prescription Status: Prescription Only (Rx) — DRAP Registered
What is Gravinate 50mg Tablet?
Gravinate 50mg contains Dimenhydrinate — a first-generation antihistamine with strong antiemetic (anti-nausea) and vestibular suppressant properties. It works by acting on two key targets simultaneously — blocking histamine H1 receptors in the inner ear to reduce the dizziness and balance disturbances that trigger nausea, and suppressing the vomiting centre in the brain to prevent and relieve nausea and vomiting directly. Gravinate 50mg is used for the prevention and treatment of nausea, vomiting, and dizziness associated with motion sickness (سفر کی بیماری), vertigo (چکر آنا), and post-surgical recovery. Being a first-generation antihistamine, it causes significant sedation — a property that is therapeutically useful in some situations but requires important precautions regarding driving and daily activities.
What is Gravinate 50mg Used For?
- Motion sickness — prevention and treatment of nausea, vomiting, and dizziness during travel by car, bus, boat, or plane (سفر کی متلی اور قے)
- Vertigo — reducing dizziness and associated nausea in vestibular disorders including labyrinthitis and Ménière's disease (چکر آنا)
- Post-operative nausea and vomiting — relief of nausea and vomiting following surgery or anaesthesia
- Nausea and vomiting of pregnancy — used under strict medical supervision for morning sickness when other measures are insufficient (حمل کی متلی — صرف ڈاکٹر کے مشورے پر)
- Radiation-induced nausea — symptomatic relief of nausea associated with radiation therapy
How Does Gravinate 50mg Work?
Histamine H1 Receptor Blockade in the Inner Ear: The inner ear contains a complex balance system — the vestibular apparatus — that detects motion and position. In motion sickness and vertigo, conflicting or excessive motion signals from the inner ear trigger histamine release that activates the vomiting centre in the brain. Dimenhydrinate blocks histamine H1 receptors in the vestibular pathways — reducing the sensitivity of the inner ear to motion signals and interrupting the chain of events that leads to nausea, vomiting, and dizziness.
Central Vomiting Centre Suppression: Dimenhydrinate also has direct anticholinergic (antimuscarinic) properties that suppress activity in the chemoreceptor trigger zone and the vomiting centre in the brainstem — reducing the brain's ability to initiate the vomiting reflex regardless of the triggering cause. This dual central and peripheral action makes Dimenhydrinate effective against multiple causes of nausea and vomiting.
Sedative Effect: As a first-generation antihistamine, Dimenhydrinate readily crosses the blood-brain barrier — producing significant CNS sedation. While this is a side effect in most contexts, it can be therapeutically useful in motion sickness and post-operative settings where rest and calm are beneficial to recovery.
Dosage and Administration
⚠️ Always take exactly as prescribed by your doctor. Never exceed the recommended dose. Do not drive or operate machinery after taking Gravinate — it causes significant drowsiness.
| Indication | Usual Adult Dose | Frequency | Maximum Daily Dose |
|---|---|---|---|
| Motion sickness prevention | 1–2 tablets (50–100mg) | Every 4–6 hours | 400mg |
| Motion sickness treatment | 1–2 tablets (50–100mg) | Every 4–6 hours | 400mg |
| Vertigo | 1–2 tablets (50–100mg) | Every 4–6 hours | 400mg |
| Post-operative nausea | As prescribed | Every 4–6 hours | As directed |
Critical Dosing Rules:
- For motion sickness prevention, take the first dose 30 minutes before travel begins — taking it after symptoms start is significantly less effective
- Never exceed 400mg in 24 hours — higher doses cause serious CNS toxicity including confusion, hallucinations, and seizures
- Elderly patients are significantly more sensitive to anticholinergic and sedative effects — use the lowest effective dose and monitor closely
- Do not use for more than a few consecutive days without medical review — prolonged use increases the risk of tolerance and anticholinergic side effects
- Children's dosing is strictly weight and age-based — never give adult doses to children without specific medical instruction
How to Take:
- Swallow the tablet whole with a full glass of water
- May be taken with or without food — taking with food reduces stomach discomfort
- For motion sickness, take 30 minutes before the journey begins
- Avoid alcohol completely during treatment — dangerous additive sedation
- Do not drive, operate machinery, or make important decisions after taking Gravinate
Active Ingredients
| Ingredient | Strength per Tablet |
|---|---|
| Dimenhydrinate | 50mg |
Who Should NOT Take Gravinate 50mg?
Do not take if you:
- Are allergic to Dimenhydrinate, Diphenhydramine, or any ingredient in the tablet
- Have acute asthma attack or severe COPD — anticholinergic effects thicken airway secretions
- Have acute narrow-angle glaucoma
- Have severe urinary retention or enlarged prostate causing urinary obstruction
- Have epilepsy or history of seizures — Dimenhydrinate lowers seizure threshold
- Are taking MAO inhibitors — serious interaction risk
- Are under 2 years of age — not recommended
Always consult your doctor before taking Gravinate if you have:
- Asthma or chronic respiratory disease (سانس کی بیماری) — anticholinergic effects may worsen breathing
- Open-angle glaucoma (آنکھوں کا دباؤ)
- Enlarged prostate or urinary difficulties (پروسٹیٹ کا بڑھنا)
- Heart disease or irregular heartbeat (دل کی بیماری) — Dimenhydrinate can prolong QT interval
- Liver or kidney disease
- Hypertension (ہائی بلڈ پریشر)
- Thyroid disease
- Are pregnant — particularly in the third trimester
- Are breastfeeding — Dimenhydrinate passes into breast milk
- Are elderly — highly sensitive to anticholinergic effects and falls risk
- Are taking other sedatives, antihistamines, or CNS depressants
Side Effects
Common Side Effects:
- Drowsiness or sedation — most common and expected effect; avoid driving or hazardous activities
- Dry mouth (منہ کا خشک ہونا) — anticholinergic effect; drink water frequently
- Dizziness or light-headedness — vestibular suppressant effect
- Blurred vision — anticholinergic effect; usually temporary
- Constipation — anticholinergic effect
- Urinary hesitancy — difficulty starting urination; particularly in men with enlarged prostate
- Headache — usually mild and temporary
- Reduced concentration and coordination — avoid activities requiring mental alertness
Serious Side Effects — Stop Taking and Seek Medical Help Immediately:
- Severe CNS toxicity — confusion, hallucinations, agitation, or seizures — sign of Dimenhydrinate overdose or toxicity; this is a medical emergency (طبی ہنگامی صورتحال)
- Acute urinary retention — complete inability to urinate — anticholinergic emergency particularly in elderly men with prostate enlargement
- Cardiac arrhythmia — irregular or very fast heartbeat, palpitations, or chest pain — Dimenhydrinate can prolong QT interval at higher doses
- Severe allergic reaction — swelling of face, lips, tongue or throat, difficulty breathing, widespread rash (یہ طبی ہنگامی صورتحال ہے)
- Acute narrow-angle glaucoma attack — sudden severe eye pain, blurred vision, halos around lights — stop immediately and seek emergency ophthalmology care
- Paradoxical excitation — particularly in children — restlessness, agitation, insomnia, and irritability instead of sedation; stop and consult doctor
- Severe respiratory depression — dangerous in patients with underlying respiratory disease; seek emergency care immediately
Drug Interactions
| Medicine / Substance | Possible Interaction |
|---|---|
| MAO Inhibitors (e.g., Phenelzine, Tranylcypromine) | Contraindicated — prolongs and intensifies anticholinergic effects of Dimenhydrinate; serious toxicity risk |
| Other antihistamines (e.g., Chlorpheniramine, Promethazine) | Additive sedation and anticholinergic effects — avoid combining |
| Benzodiazepines (e.g., Diazepam, Alprazolam) | Additive CNS depression and sedation — dangerous respiratory depression risk; avoid combination |
| Opioid analgesics (e.g., Tramadol, Codeine, Morphine) | Additive CNS and respiratory depression — serious sedation and breathing risk; use only under medical supervision |
| Anticholinergic medicines (e.g., Oxybutynin, Hyoscine) | Additive anticholinergic effects — severe dry mouth, constipation, urinary retention, and confusion risk |
| Antidepressants — TCAs (e.g., Amitriptyline) | Additive anticholinergic and sedative effects — increased toxicity risk particularly in elderly |
| Antipsychotics (e.g., Haloperidol, Quetiapine) | Additive QT prolongation, sedation, and anticholinergic effects — monitor carefully |
| Ototoxic medicines (e.g., Aminoglycoside antibiotics, Cisplatin) | Dimenhydrinate may mask the early warning symptoms of ototoxicity — hearing damage may go undetected; avoid combining |
| Antihypertensives | Additive blood pressure lowering — increased dizziness and fall risk; monitor blood pressure |
| Alcohol (شراب) | Severely enhances CNS depression and sedation — extremely dangerous combination; avoid completely during treatment |
Storage Instructions
- Store below 25°C in a cool, dry place
- Protect from light, moisture, and direct sunlight
- Keep in original blister pack until use
- Keep out of reach of children (بچوں کی پہنچ سے دور رکھیں)
- Do not use after the expiry date printed on the pack
Frequently Asked Questions (FAQs)
Q: When should I take Gravinate 50mg for motion sickness? Take Gravinate 30 minutes before your journey begins — taking it after nausea has already started is significantly less effective as prevention works better than treatment once symptoms develop.
Q: Can I drive after taking Gravinate 50mg? No — Gravinate causes significant drowsiness and impairs concentration and coordination; never drive, operate machinery, or perform any activity requiring full alertness after taking this medicine.
Q: Is Gravinate 50mg safe during pregnancy? Dimenhydrinate is sometimes used under strict medical supervision for pregnancy-related nausea — however it must never be taken during the third trimester or without your obstetrician's explicit advice as it may affect the newborn.
Q: Can Gravinate 50mg be used for vertigo? Yes — Gravinate effectively reduces the dizziness and nausea associated with vertigo by suppressing inner ear sensitivity; however persistent or recurrent vertigo should always be evaluated by a doctor to identify and treat the underlying cause.
Medical Disclaimer: This information is for general awareness only and does not replace advice from your doctor or pharmacist. Always take Gravinate 50mg exactly as prescribed and never exceed the recommended daily dose. If you experience confusion, hallucinations, or seizures after taking this medicine, seek emergency medical care immediately.