Bilastine Zentiva

What Is Bilastine Zentiva and What Is It Used For?

Bilastine Zentiva belongs to a class of medicines called second-generation antihistamines, also known as non-sedating antihistamines. The active substance, bilastine, works by selectively blocking histamine H1 receptors on cells throughout the body. When your immune system encounters an allergen such as pollen, dust mites, or pet dander, it releases histamine, which triggers the familiar symptoms of an allergic reaction. By blocking the receptor where histamine binds, bilastine effectively reduces or prevents these symptoms from occurring.

The primary indications for Bilastine Zentiva are allergic rhinoconjunctivitis and urticaria. Allergic rhinoconjunctivitis encompasses both seasonal allergic rhinitis (hay fever), caused by outdoor allergens such as tree and grass pollen, and perennial allergic rhinitis, triggered by year-round allergens like house dust mites, mould spores, and animal dander. Symptoms typically include sneezing, nasal congestion, runny nose (rhinorrhoea), and itchy, watery, or red eyes.

Urticaria, commonly known as hives, presents as raised, itchy welts (wheals) on the skin that can appear anywhere on the body. Bilastine Zentiva is effective for both acute urticaria and chronic spontaneous urticaria, providing relief from the intense itching and reducing the size and number of wheals. The European Academy of Allergy and Clinical Immunology (EAACI) and the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines recommend second-generation antihistamines, including bilastine, as first-line treatment for both conditions.

Unlike first-generation antihistamines such as chlorpheniramine or diphenhydramine, bilastine does not significantly cross the blood-brain barrier. This means it is far less likely to cause drowsiness, sedation, or impaired cognitive function. Multiple clinical studies have confirmed that bilastine at the recommended 20 mg dose does not impair psychomotor performance, making it suitable for patients who need to remain alert throughout the day, including those who drive or operate machinery.

Bilastine Zentiva is manufactured by Zentiva, a major European pharmaceutical company. The product contains the same active ingredient as the originator brand Ilaxten and other bilastine generic formulations, and is bioequivalent, meaning it delivers the same clinical effect at the same dose.

What Should You Know Before Taking Bilastine Zentiva?

Contraindications

You must not take Bilastine Zentiva if you are allergic (hypersensitive) to bilastine or to any of the other ingredients in the tablet. Although true hypersensitivity to bilastine is rare, if you have experienced any allergic reaction to this medicine in the past, including skin rash, swelling, or difficulty breathing, you should not take it again and should inform your healthcare provider immediately.

There are no absolute contraindications based on specific medical conditions beyond hypersensitivity. However, certain patient groups require special consideration. Patients with severe renal impairment (significantly reduced kidney function) should use bilastine with caution, as the kidneys play a role in eliminating the drug from the body. Your doctor may need to adjust the dosing or choose an alternative medication if your kidney function is substantially impaired.

Warnings and Precautions

There are several important warnings and precautions to be aware of when taking Bilastine Zentiva. The most critical relates to how and when you take the medication. Bilastine must be taken on an empty stomach, meaning at least one hour before or two hours after eating food. Taking bilastine with food reduces its bioavailability by approximately 30%, which means significantly less of the drug reaches your bloodstream and the therapeutic effect is reduced.

Similarly, you should avoid taking bilastine with grapefruit juice or other fruit juices, as these interact with organic anion transporting polypeptides (OATPs) in the intestinal wall and can reduce the absorption of bilastine. Water is the recommended fluid for taking this medication.

Patients with moderate renal impairment should be monitored, as plasma concentrations of bilastine may be increased. In clinical pharmacokinetic studies, co-administration with P-glycoprotein (P-gp) inhibitors such as ketoconazole, erythromycin, and cyclosporine increased the plasma levels of bilastine. While this increase was not associated with significant changes in the safety profile in clinical trials, caution is warranted, and your doctor should be informed about all medications you are taking.

Pregnancy and Breastfeeding

If you are pregnant, think you may be pregnant, or are planning to become pregnant, you should consult your doctor before taking Bilastine Zentiva. There are limited data on the use of bilastine in pregnant women. Animal reproductive toxicity studies have not shown any direct harmful effects on pregnancy, embryonic or foetal development, birth, or postnatal development. However, as a precautionary measure, bilastine should preferably be avoided during pregnancy unless your doctor considers it clearly necessary.

Bilastine has been shown to be excreted in the milk of animals. It is not known whether bilastine is excreted in human breast milk. A decision must be made whether to discontinue breastfeeding or to discontinue bilastine therapy, taking into account the benefit of breastfeeding for the child and the benefit of therapy for the mother. Your healthcare provider can help you weigh these considerations and decide on the safest course of action.

How Does Bilastine Zentiva Interact with Other Drugs?

Bilastine has a comparatively favourable drug interaction profile compared to many other antihistamines. It is not significantly metabolised by the cytochrome P450 (CYP) enzyme system, which is responsible for the metabolism of many drugs. This is an important advantage because CYP-mediated interactions are a common source of drug-drug interactions. Since bilastine is primarily excreted unchanged, there is a lower risk of metabolic interactions with other medications.

However, bilastine is a substrate for P-glycoprotein (P-gp) and organic anion transporting polypeptides (OATPs). These are transporter proteins that play a role in how the drug is absorbed, distributed, and eliminated from the body. Medications that inhibit these transporters can increase the plasma concentration of bilastine, potentially leading to enhanced effects or side effects.

Major Interactions

Minor Interactions

It is important to note that interaction studies with ketoconazole and erythromycin, while showing increased bilastine plasma concentrations, did not demonstrate clinically relevant changes to the ECG (QTc interval) or an increase in adverse events. Nevertheless, your doctor should be aware of all medications you are currently taking, including over-the-counter drugs, herbal supplements, and vitamins, to assess any potential for interaction.

What Is the Correct Dosage of Bilastine Zentiva?

Bilastine Zentiva should always be taken exactly as your doctor has instructed. The medication is designed as a once-daily treatment, providing consistent 24-hour coverage against allergy symptoms. The pharmacokinetic profile of bilastine supports this dosing regimen, with the drug reaching peak plasma concentration (Cmax) approximately 1.3 hours after administration and having an elimination half-life of approximately 14.5 hours.

Adults

For seasonal allergic rhinitis, treatment is typically continued throughout the pollen season. The duration depends on the specific allergen causing symptoms and the severity of the allergy. For perennial allergic rhinitis, year-round treatment may be appropriate. For chronic urticaria, long-term treatment under medical supervision may be necessary, and the duration should be determined by your healthcare provider based on the persistence and severity of symptoms.

Children and Adolescents

Bilastine Zentiva 20 mg tablets are not recommended for children under 12 years of age. The safety and efficacy of this tablet formulation have not been established in children below 12 years. For younger children requiring antihistamine treatment, alternative formulations or different antihistamines should be used as recommended by a paediatrician. Some bilastine products are available as oral solution (10 mg formulation) for children aged 6 to 11 years in certain markets, but this is a separate product from Bilastine Zentiva 20 mg tablets.

Elderly Patients

No dose adjustment is required for elderly patients. Clinical experience in patients over 65 years of age is limited but available data do not suggest any need for dose modification. The non-sedating profile of bilastine makes it a potentially suitable choice for older adults, as sedation from first-generation antihistamines can increase the risk of falls and cognitive impairment in this population.

Missed Dose

If you forget to take a dose of Bilastine Zentiva, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take the next dose at the usual time. Do not take a double dose to make up for a missed one. The once-daily dosing schedule means that a single missed dose is unlikely to significantly affect your allergy symptom control, but consistent daily dosing provides the best results.

Overdose

In the event of an overdose, seek immediate medical attention or contact your local poison control centre. In clinical studies, bilastine has been administered at doses up to 220 mg (11 times the recommended dose) without serious adverse effects. However, at doses of 100 mg and above, some subjects reported increased drowsiness. There is no specific antidote for bilastine overdose. Treatment is supportive and symptomatic, and may include gastric lavage and monitoring of vital signs.

What Are the Side Effects of Bilastine Zentiva?

Like all medicines, Bilastine Zentiva can cause side effects, although not everybody gets them. Clinical trials involving over 4,800 patients have established that bilastine has an excellent safety profile at the recommended 20 mg dose. Many of the side effects reported occurred at frequencies comparable to those seen with placebo (an inactive substance), indicating that bilastine is very well tolerated.

The following side effects have been reported in clinical trials and post-marketing surveillance. They are organised by frequency according to the standard medical classification system used by the European Medicines Agency (EMA):

It is important to recognise that headache and drowsiness, while classified as "common," occurred in clinical trials at rates very similar to those in the placebo group. This suggests that these symptoms may not always be directly caused by the medication. A comprehensive meta-analysis published in the British Journal of Clinical Pharmacology confirmed that bilastine 20 mg does not cause statistically significant sedation compared to placebo.

No clinically relevant effects on the QTc interval (a measure of heart rhythm) have been observed with bilastine at doses up to 100 mg (five times the recommended dose). This is an important safety consideration, as some older antihistamines have been associated with cardiac arrhythmias.

If you experience any side effects not listed here, or if any of the side effects become severe or bothersome, please consult your doctor or pharmacist. You can also report side effects directly to your national pharmacovigilance authority. By reporting side effects, you help provide more information on the safety of this medicine.

How Should You Store Bilastine Zentiva?

Proper storage of Bilastine Zentiva is essential to ensure that the medication remains effective and safe throughout its shelf life. The following storage conditions should be observed:

• Temperature: Store below 30°C (86°F). Do not freeze the tablets.
• Protection: Keep the tablets in the original blister packaging to protect from moisture and light. Do not transfer the tablets to other containers.
• Children: Keep out of the sight and reach of children. Store in a location where children cannot access the medication.
• Expiry date: Do not use Bilastine Zentiva after the expiry date printed on the packaging and blister. The expiry date refers to the last day of that month.
• Disposal: Do not throw away any medicines via household waste or wastewater. Ask your pharmacist how to dispose of medicines you no longer need. These measures will help protect the environment.

If the tablets have changed colour, show signs of damage, or the packaging has been tampered with, do not use the medication and return it to your pharmacy for safe disposal. Bilastine tablets should appear uniform in colour and shape. Any noticeable changes may indicate degradation of the active ingredient.

What Does Bilastine Zentiva Contain?

Understanding the full composition of your medication can be important, particularly if you have known allergies or intolerances to specific pharmaceutical excipients. Each Bilastine Zentiva 20 mg tablet contains the following:

Active Ingredient

• Bilastine 20 mg – the active pharmaceutical ingredient responsible for the antihistamine effect. Bilastine (chemical name: 2-[4-(2-(4-(1-(2-ethoxyethyl)-1H-benzimidazol-2-yl)piperidin-1-yl)ethyl)phenyl]-2-methylpropionic acid) is a piperidine-benzimidazole derivative with high selectivity for the histamine H1 receptor.

Excipients (Inactive Ingredients)

The inactive ingredients serve various pharmaceutical functions such as binding the tablet, aiding disintegration, and facilitating manufacturing. Common excipients in bilastine tablet formulations include:

• Microcrystalline cellulose – a filler and binder that provides structure to the tablet
• Croscarmellose sodium – a disintegrant that helps the tablet break apart in the stomach for proper absorption
• Colloidal anhydrous silica – a flow agent used during manufacturing
• Magnesium stearate – a lubricant that prevents the tablet from sticking to the manufacturing equipment

The exact excipient list may vary slightly between batches or formulations. Always check the patient information leaflet that comes with your specific pack for the definitive list. If you are allergic to any of the listed excipients, inform your doctor or pharmacist before taking this medication.