Zentel 400mg (Albendazole)

Zentel 400 is GSK's albendazole 400 mg chewable tablet, made in India by GlaxoSmithKline Pharmaceuticals Ltd. Albendazole is a benzimidazole worm medicine: it reduces the worms' uptake of glucose, so they run out of energy and die. The Indian label gives one tablet as a single dose for roundworm, hookworm, whipworm and pinworm (threadworm) in adults and children over 2. We sell Zentel 400 in packs of 6, 12 and 24 tablets, from $1.67 a tablet before shipping.

Read this before you order. Albendazole is not the right medicine for every worm, and a stool test (or a tape test for pinworm) should come first. In the US, albendazole is approved only for two tapeworm larval infections (neurocysticercosis and hydatid disease); its use for intestinal worms comes from CDC and WHO guidance. Pregnancy is a contraindication on the Indian label for this pack. This page covers which worms one tablet treats, how many tablets each infection needs, how to take it, the warnings from the Indian and US labels, who should not take it, prices against US generic albendazole, and the legal status in the US, UK, Australia and Canada. Sources are listed at the end.

Zentel 400 at a glance

Price per tablet

Prices below are as of October 2026; the pack selector shows the current price.

All three packs are under $149, so a single pack carries $25 shipping. With shipping, the smallest order costs $40.

How many tablets you need. Under the Indian label, one person with roundworm, hookworm, whipworm or pinworm needs one tablet, and a second course if not cured after three weeks. Strongyloidiasis and tapeworms take three tablets (one a day for 3 days), and liver flukes six (one twice a day for 3 days). The CDC repeats the pinworm dose after two weeks. So the 6 pack covers the longest of these short courses for one person, or single doses for a small household. The 12 and 24 packs are more than most people need. Doses differ by age and by worm, so leftover tablets are not automatically right for someone else, and we advise against keeping them to treat yourself later without a diagnosis. Check the expiry date on the blisters when your order arrives.

Compared with US generic albendazole

There is no FDA-approved Zentel and no FDA-approved 400 mg albendazole tablet in the US. FDA-approved albendazole comes as 200 mg film-coated tablets from several generic makers, so a 400 mg dose is two tablets. Albenza, the original US brand, is listed as discontinued in Drugs@FDA.

NADAC is the average price US pharmacies pay to buy a medicine, not the price at the counter. In the NADAC file effective 21 October 2026, generic albendazole 200 mg cost pharmacies $4.12540 a tablet, the same rate for all five listed products; there is no row for Albenza. At that rate one 400 mg dose is about $8.25 and a 3-day course about $24.75 (our arithmetic). Put plainly: if one person needs one dose, a US prescription for the generic will often cost less in total than our smallest order with shipping. If you are in the US and have a prescription, compare cash prices at a local pharmacy before you order from abroad. We have not seen data comparing Zentel 400 with US generic albendazole for bioequivalence, so treat them as the same dose, not as interchangeable products.

Which worms one tablet treats, and how many tablets

Zentel is the only strength in its family on our site. The table sets the Indian label doses against the CDC. Our tablet counts assume the 400 mg tablet.

The CDC notes that albendazole is not FDA approved for roundworm, hookworm or whipworm. For strongyloidiasis, ivermectin is the US-labelled treatment, and in the Stromectol label's studies a single ivermectin dose cured more patients than albendazole 200 mg twice daily for 3 days; ask your doctor (Ivercor 12mg is our ivermectin page). For tapeworms, the CDC prefers praziquantel (Biltree 600mg). For pinworm, mebendazole 100 mg is the UK and US labelled dose (Mebex 100mg). Our intestinal worm treatment guide explains how each worm is diagnosed.

The WHO recommends single-dose albendazole 400 mg (or mebendazole 500 mg), once or twice a year, for children in areas where at least 20% have worm infections, with a half dose (200 mg) for children under 24 months. That is mass treatment in high-risk areas, not a reason to deworm yourself routinely elsewhere.

How to take Zentel 400

1. Get the worm identified first, and take the dose your doctor advises.
2. Chew the tablet before swallowing (Indian label 8.4: "To be chewed before swallowing"). The label says young children who find it hard to swallow should be encouraged to chew it with a little water, or the tablet may be crushed.
3. Food: the Indian label says no fasting or purging is needed for intestinal worms, and says to take it with meals for the long courses used for cysts. The US label, written for neurocysticercosis and hydatid disease (liver, lung and peritoneal cysts), says to take it with food; a fatty meal raised levels of the active form up to 5-fold on average. The CDC advises taking albendazole for intestinal worms on an empty stomach. The labels and the CDC differ, so ask your prescriber which applies to you.
4. Women who could become pregnant: the Indian label says to start a short course in the first week of a period or after a negative pregnancy test. The US label recommends a pregnancy test before starting, and effective contraception during treatment and for 3 days after the last dose. For long courses, the Indian label advises a negative pregnancy test before each cycle and contraception during and within one month after treatment.
5. If you are still infected three weeks after treatment, the Indian label says a second course is indicated. Ask your doctor about a follow-up stool test.
6. Albendazole can cause dizziness; take this into account before driving or using machines (Indian label 4.7).

Children, older people, liver and kidney disease

• Children aged 1 to 2: the Indian label dose is 200 mg, half of a Zentel 400 tablet, and the WHO also uses a half dose under 24 months. We have not confirmed that the tablet is scored, so a whole Zentel 400 tablet is not suitable for this age group; ask a doctor. The Indian label gives no dose for children under 1. The CDC says: "The safety of albendazole in children less than 6 years old is not certain. Studies of the use of albendazole in children as young as one year old suggest that it is safe."
• Children under 6, long courses: the Indian label says high-dose use under 6 years is not recommended, because experience is limited.
• Age 65 and over: the Indian label says data are limited but there is no evidence that older people need a different dose.
• Liver disease: the Indian label says people with hepatic impairment "must seek medical advice before starting the treatment". The US label says people with liver disease are at increased risk of bone marrow suppression.
• Kidney disease: the Indian label says no dose change is needed, but patients with kidney impairment should be carefully monitored.

Side effects

The Indian label lists side effects separately for short courses (intestinal worms) and long courses (cysts). For a single 400 mg tablet, the short-course list applies.

The Indian label says the frequencies for the rarest reactions come mainly from reports after marketing and are reporting rates, not true frequencies. On long courses, the Indian label adds very common headache and raised liver enzymes, common dizziness, stomach upset, fever and reversible hair loss, uncommon low white cell counts and hepatitis, and very rare pancytopenia, aplastic anaemia and agranulocytosis. In the US label's trials in hydatid disease and neurocysticercosis, both treated with long courses, liver enzymes rose in 16% of hydatid patients and headache occurred in 11% of neurocysticercosis patients (Table 2). These long-course figures do not describe a single 400 mg dose.

The tablets contain the colour sunset yellow FCF, which the Indian label says may cause allergic-type reactions.

When to get urgent help

• Swelling of the lips, tongue or throat, trouble breathing or swallowing, widespread rash or hives: possible serious allergic reaction.
• Blistering, peeling or a spreading rash with sores in the mouth or eyes: possible Stevens-Johnson syndrome or erythema multiforme, both listed on the Indian and US labels.
• A seizure, a severe headache, confusion or new weakness after a dose. The Indian label warns that albendazole may uncover tapeworm cysts in the brain that nobody knew about, particularly in areas where tapeworm infection is common. It says seizures, increased pressure in the brain and focal signs "may occur soon after treatment", and that steroid and anticonvulsant treatment should be started immediately.
• Yellow skin or eyes, or dark urine. Both labels list hepatitis; these signs are our general advice for spotting it.
• Fever, sore throat, frequent infections, or unusual bruising or bleeding: possible effect on the bone marrow. The US label reports deaths from granulocytopenia or pancytopenia (very low white cell or all blood cell counts); its approved uses are long courses. These signs are our general advice for spotting it.
• Someone has taken too many tablets, or a child has swallowed them. The Indian label has no overdose data and says to follow the national poisons centre's advice: call a poison line (US 1-800-222-1222, Australia 13 11 26) or seek emergency care.

Tell the emergency staff that the medicine was albendazole 400 mg, how much was taken and when.

Who should not take Zentel 400

Never take it if:

• you are allergic to albendazole or any ingredient of the tablet (Indian label 4.3), or to any benzimidazole medicine, such as mebendazole (US label 4)
• you are pregnant or think you may be pregnant. The Indian label says Zentel "should not be administered during pregnancy, or in women thought to be pregnant" (4.3). The US label says albendazole "may cause fetal harm" (5.2), based on birth defects in rat and rabbit studies

Pregnancy wording differs by source. The US label does not list pregnancy as a contraindication, and says published human data on single-dose use later in pregnancy have not identified drug-associated risks. The WHO includes women in the second and third trimesters of pregnancy in its mass deworming programmes. The Indian label for this pack still says not to use it in pregnancy, so see a doctor if you are or may be pregnant.

Do not take it, or only on a doctor's advice:

• Possible tapeworm cysts in the brain or eye (neurocysticercosis). The US label says people with risk factors for neurocysticercosis should be evaluated before starting treatment (5.6). Having lived in or travelled to areas where pork tapeworm is common is one such factor (our example). The US label says the eye should be examined for retinal lesions before treating neurocysticercosis, because the dying parasite can damage the retina (5.4).
• Liver disease or raised liver enzymes. The Indian label says people with hepatic impairment must seek medical advice first. The US label says people with liver disease are at increased risk of bone marrow suppression, and people with raised liver enzymes at increased risk of liver injury and bone marrow suppression. The US label's blood count and liver test schedule (start of each 28-day cycle and every 2 weeks) is written for its long courses; the label does not cover a single 400 mg dose, so ask your doctor about testing.
• Breastfeeding. The Indian label says adequate data are not available. The US label says levels in breast milk are low, and that the benefits of breastfeeding should be weighed against the mother's need for treatment.
• Children under 2. See the children section above.
• Taking interacting medicines (below).

Medicines that interact

• Raise albendazole levels: cimetidine, praziquantel and dexamethasone (Indian label 4.5). In the US label studies, dexamethasone raised levels of the active form by about 56%, praziquantel by about 50%, and cimetidine about 2-fold in bile and cyst fluid.
• May lower albendazole levels: ritonavir, phenytoin, carbamazepine and phenobarbital. The Indian label says the clinical relevance is unknown but treatment may work less well, especially for cyst infections.
• Theophylline: the US label recommends monitoring theophylline levels during and after treatment.

Tell your doctor or pharmacist about every medicine you take.

Prescription and legal status

• US: albendazole 200 mg tablets are prescription medicines, approved for neurocysticercosis and hydatid disease. There is no 400 mg tablet, and Albenza is listed as discontinued in Drugs@FDA. The FDA says personal importation of unapproved medicines is illegal in most circumstances.
• UK: we found no albendazole product on the electronic medicines compendium, and the NHS medicines dictionary lists Zentel 400 mg chewable tablets as an import with no licensing authority. Mebendazole is the UK-licensed threadworm treatment (Ovex is a pharmacy medicine).
• Australia: healthdirect lists Zentel 200 mg tablets and Eskazole 400 mg chewable tablets as Schedule 4 prescription-only medicines, not on the PBS. We did not find a 400 mg Zentel product on the Australian register.
• Canada: the only albendazole product we found in Health Canada's Drug Product Database is a veterinary suspension. Zentel is supplied through the Special Access Program, where it was requested 146 times in 2025.
• India: the carton in our product photo carries the Rx symbol, the Indian label is "For the use only of Registered Medical Practitioners or a Hospital or a Laboratory", and Tata 1mg and Truemeds mark it as needing a prescription.

Check the rules where you live before ordering.

Buying genuine Zentel 400

The MHRA warns that "Any medicine not authorised for sale in the UK can be unsafe or ineffective and there is no way of knowing what is in them or the negative health effects they can have", and it advises UK buyers: "Only use UK-registered pharmacies, including online pharmacies displaying the official green cross logo". That warning covers Zentel 400, which is not authorised in the UK. When your order arrives, check that each blister says Zentel and albendazole, names GSK, and shows a batch number and an expiry date, and that the tablet is a chewable 400 mg tablet. If the strength or ingredient is different, do not take it and contact us. These checks cannot prove that tablets are genuine, because counterfeiters copy packaging. A worm treatment can fail without obvious signs, so ask your doctor about a follow-up stool test. If a batch causes unusual symptoms, seek medical advice and report it to your medicines regulator (the MHRA Yellow Card scheme in the UK, FDA MedWatch in the US, the TGA in Australia or Health Canada) as well as to us.

Delivery

We ship Zentel 400 to the US, UK, Australia and Canada in plain packaging with tracking. Standard delivery takes 7 to 14 business days. Shipping costs a flat $25 on orders under $149 and is free from $149. If you have symptoms now, a local doctor or pharmacy will be faster. See our shipping page and refund policy.

Related guides

• Zentel (albendazole): uses, dosage and where to buy
• Albendazole tablets guide
• Mebendazole vs albendazole for worms
• Intestinal worm treatment: diagnosis, medicines and prevention
• Buying Zentel (albendazole) in the USA

Related products: Aldol 400mg (albendazole), Bandy-Plus 12 (albendazole with ivermectin), Mebex 100mg and Mebmox 500 (mebendazole), Biltree 600mg (praziquantel). Browse all antiparasitic medicines.

Sources

• ZENTEL (albendazole) uncoated chewable tablets and oral suspension, Indian prescribing information, GlaxoSmithKline Pharmaceuticals Ltd, version ZEN/PI/IN/2026/01, revised 8 July 2026: sections 2, 4.1 to 4.9, 5.1 to 5.3, 8.3, 8.4. GSK India
• Albendazole tablets, US prescribing information, Edenbridge Pharmaceuticals, DailyMed setid 6c48fd89-cb40-477c-8a78-15cbe0df6faa, version 43 (effective 10 July 2026): sections 1, 2, 4, 5.1 to 5.6, 6.1, 6.2, 7, 8.1 to 8.3, 12.3, 17. DailyMed
• US Centers for Disease Control and Prevention. Clinical care of soil-transmitted helminths (reviewed 3 June 2024), Clinical overview of pinworm infection (reviewed 20 February 2024) and Clinical care of taeniasis (reviewed 3 May 2024). CDC STH, CDC pinworm, CDC taeniasis
• World Health Organization. Soil-transmitted helminth infections fact sheet, 18 January 2023; e-Library of Evidence for Nutrition Actions, Deworming in children (updated 9 August 2023), from the WHO 2017 guideline on preventive chemotherapy. WHO fact sheet, WHO eLENA
• STROMECTOL (ivermectin) tablets, US prescribing information, DailyMed setid 681888c9-af79-4b7d-ae80-c3f4f6f1effd, version 20 (09/2024): Clinical Studies (strongyloidiasis comparison with albendazole).
• Centers for Medicare and Medicaid Services. National Average Drug Acquisition Cost (NADAC) 2026: albendazole 200 mg tablet, NDCs 00591271202, 31722093502, 42799011002, 43598045202 and 72205005108, $4.12540 each, effective 21 October 2026; no rows for Albenza. data.medicaid.gov
• US Food and Drug Administration, Drugs@FDA via openFDA: Albenza (NDA 020666, discontinued) and generic albendazole 200 mg tablets (prescription); searched 21 October 2026.
• NHS Dictionary of Medicines and Devices: Zentel 400mg chewable tablets, imported, licensing authority none; electronic medicines compendium search for albendazole, no results, 21 October 2026. dm+d
• healthdirect Australia: Zentel 200 mg and Eskazole 400 mg, Schedule 4, not PBS; TGA ARTG 43928 (Zentel albendazole 200 mg chewable tablet). healthdirect
• Health Canada. Drug Product Database (albendazole: veterinary Valbazen suspension only) and Special Access Program, drugs most often requested, 1 January to 31 December 2025 (modified 7 May 2026). Health Canada
• Indian listings for Zentel 400 mg chewable tablet: PharmEasy, Truemeds and Tata 1mg, checked 21 October 2026; carton and blisters in our product photo.
• MHRA. 20 million illegal erectile dysfunction pills seized as MHRA warns against risky online buys, 13 February 2026. GOV.UK
• US Food and Drug Administration. Personal Importation. FDA

This page is for information and is not medical advice. Albendazole is a prescription medicine in the US, Australia and India, and the Zentel carton carries the Rx symbol. See a doctor to identify the worm, choose the right dose for each person, and check that the treatment worked.