Tetrazin
Generic Name
Cetirizine Hydrochloride
Manufacturer
Square Pharmaceuticals Ltd.
Country
Bangladesh
Loading images...
Price Details
Current market pricing information
| Variant | Unit Price | Strip Price |
|---|---|---|
| tetrazin 25 mg tablet | ৳ 35.00 | ৳ 350.00 |
| tetrazin 125 mg tablet | ৳ 20.00 | ৳ 200.00 |
Description
Overview of the medicine
Tetrazin (Cetirizine) is a potent, selective, second-generation antihistamine used for the symptomatic relief of seasonal and perennial allergic rhinitis, chronic idiopathic urticaria, and other allergic conditions. It provides 24-hour relief with a single daily dose and has minimal sedative effects.
Uses & Indications
Dosage
Adults
10 mg once daily, or 5 mg twice daily. Maximum daily dose is 10 mg.
Elderly
Start with 5 mg once daily due to potential age-related decline in renal function. Dose adjustment should be based on individual renal function.
Renal_impairment
Moderate renal impairment (creatinine clearance 30-49 ml/min): 5 mg once daily. Severe renal impairment (creatinine clearance <30 ml/min): 5 mg every other day. Contraindicated in end-stage renal disease (creatinine clearance <10 ml/min).
How to Take
Tetrazin can be taken orally with or without food. For syrup and drops, use the provided measuring cup or dropper to ensure accurate dosing.
Mechanism of Action
Cetirizine, a carboxylic acid metabolite of hydroxyzine, acts as a selective peripheral H1-receptor antagonist. It effectively inhibits the release of histamine from mast cells and reduces inflammatory mediator release, thereby preventing the effects of histamine such as vasodilation, increased vascular permeability, and itching.
Pharmacokinetics
Onset
20-60 minutes
Excretion
Approximately 60-70% of the dose is excreted unchanged in the urine, and a smaller amount is eliminated in the feces. Renal impairment significantly reduces clearance.
Half life
The plasma elimination half-life is approximately 8-12 hours in adults, but it can be prolonged in children, elderly patients, and individuals with renal impairment.
Absorption
Rapidly absorbed from the gastrointestinal tract following oral administration; peak plasma concentrations (Cmax) are achieved within 1 hour.
Metabolism
Minimally metabolized in the liver (less than 10% of the dose); primarily excreted unchanged.
Side Effects
Contraindications
- Known hypersensitivity to cetirizine, hydroxyzine, or any piperazine derivatives, or to any of the excipients.
- Patients with severe renal impairment (creatinine clearance <10 ml/min).
- Contraindicated during breastfeeding (as per some guidelines due to excretion into breast milk).
Drug Interactions
Ritonavir
Increased plasma concentration of cetirizine has been reported.
Theophylline (high doses, e.g., 400 mg daily)
A slight decrease in cetirizine clearance (approx. 16%) has been observed, but no significant clinical impact is generally expected at usual therapeutic doses.
Central Nervous System (CNS) depressants (e.g., alcohol, sedatives, hypnotics)
Co-administration may enhance CNS depressant effects, leading to increased drowsiness or impaired performance. Concurrent alcohol use should be avoided.
Storage
Store in a cool, dry place below 30°C, protected from light and moisture. Keep out of reach of children. Do not freeze.
Overdose
Symptoms of overdose may include drowsiness, stupor, tachycardia, tremor, urinary retention, and fatigue. In case of an overdose, symptomatic and supportive treatment should be initiated. There is no specific antidote. Gastric lavage and activated charcoal may be considered in the initial hours following ingestion. Hemodialysis is not effective in removing cetirizine.
Pregnancy & Lactation
Pregnancy Category B. Animal studies have shown no evidence of fetal harm, but there are no adequate and well-controlled studies in pregnant women. Tetrazin should be used during pregnancy only if clearly needed and after consulting a physician. Cetirizine is excreted into breast milk; therefore, its use is generally not recommended during breastfeeding due to potential risk to the infant.
Side Effects
Contraindications
- Known hypersensitivity to cetirizine, hydroxyzine, or any piperazine derivatives, or to any of the excipients.
- Patients with severe renal impairment (creatinine clearance <10 ml/min).
- Contraindicated during breastfeeding (as per some guidelines due to excretion into breast milk).
Drug Interactions
Ritonavir
Increased plasma concentration of cetirizine has been reported.
Theophylline (high doses, e.g., 400 mg daily)
A slight decrease in cetirizine clearance (approx. 16%) has been observed, but no significant clinical impact is generally expected at usual therapeutic doses.
Central Nervous System (CNS) depressants (e.g., alcohol, sedatives, hypnotics)
Co-administration may enhance CNS depressant effects, leading to increased drowsiness or impaired performance. Concurrent alcohol use should be avoided.
Storage
Store in a cool, dry place below 30°C, protected from light and moisture. Keep out of reach of children. Do not freeze.
Overdose
Symptoms of overdose may include drowsiness, stupor, tachycardia, tremor, urinary retention, and fatigue. In case of an overdose, symptomatic and supportive treatment should be initiated. There is no specific antidote. Gastric lavage and activated charcoal may be considered in the initial hours following ingestion. Hemodialysis is not effective in removing cetirizine.
Pregnancy & Lactation
Pregnancy Category B. Animal studies have shown no evidence of fetal harm, but there are no adequate and well-controlled studies in pregnant women. Tetrazin should be used during pregnancy only if clearly needed and after consulting a physician. Cetirizine is excreted into breast milk; therefore, its use is generally not recommended during breastfeeding due to potential risk to the infant.
Frequently Asked Questions
Common questions about this medicine
Pack Sizes
Shelf Life
Typically 24 to 36 months from the date of manufacture. Refer to the expiry date printed on the packaging for specific information.
Availability
Available in all retail pharmacies and hospitals in Bangladesh
Approval Status
Approved by DGDA (Bangladesh)
Patent Status
Generic available, patent expired
WHO Essential Medicine
YesClinical Trials
Cetirizine has been extensively evaluated in numerous clinical trials, demonstrating its significant efficacy in reducing symptoms of allergic rhinitis and chronic urticaria, with a favorable safety profile. Studies consistently show its rapid onset of action and sustained 24-hour effect.
Lab Monitoring
- No routine laboratory monitoring is typically required for patients taking Tetrazin. However, for patients with renal impairment, creatinine clearance should be monitored to guide dose adjustments.
Doctor Notes
- Educate patients on the proper administration of Tetrazin and the importance of adhering to the prescribed dosage.
- Advise patients about potential for drowsiness and to exercise caution with activities requiring mental alertness.
- For elderly and renally impaired patients, careful dose adjustment based on creatinine clearance is crucial.
- Emphasize avoiding concurrent alcohol consumption.
Patient Guidelines
- Do not exceed the recommended dose. If symptoms persist or worsen, consult your doctor.
- Avoid alcohol consumption while taking Tetrazin, as it may enhance drowsiness.
- Inform your doctor about all other medications, supplements, and herbal products you are taking.
- If you experience severe allergic reactions or unusual side effects, seek immediate medical attention.
Missed Dose Advice
If you miss a dose of Tetrazin, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one.
Driving Precautions
Cetirizine, though generally less sedating than first-generation antihistamines, may cause drowsiness or dizziness in some individuals. Patients should be advised to exercise caution when driving or operating heavy machinery until they know how Tetrazin affects them.
Lifestyle Advice
- Try to identify and avoid your allergy triggers (e.g., pollen, dust mites, pet dander).
- Maintain good personal hygiene and keep your living environment clean to minimize allergen exposure.
- Stay well-hydrated by drinking plenty of fluids.
Alternative Medicines in Bangladesh
Similar medicines available in the market
Global Brand Names
International brand names for this medicine. Click a brand to search for detailed information.
Other Medicines in Tetrazin Brand
Other medicines available under the same brand name
