A1

Uses

A1is used as anthelmintic against most nematodes and cestodes. It is effective against these gastro-intestinal parasites Bunostomum, Chabertia, Cooperia, Haemonchus, Ostertagia, Nematodirus, Strongyloides, Dictyocaulusviviparus, Monieziaexpansa, Liver flukes and Paramphistomes. It is also effective against different types of worms, lung flukes and lung nematodes.

A1 is also used to associated treatment for these conditions: Ascariasis, Hookworm Infection, Hydatid disease caused by Echinococcus granulosus, Neurocysticercosis caused by Taenia solium, Other specified protozoal diseases

How A1 works

A1 causes degenerative alterations in the tegument and intestinal cells of the worm by diminishing its energy production, ultimately leading to immobilization and death of the parasite. It works by binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization or assembly into microtubules. As cytoplasmic microtubules are critical in promoting glucose uptake in larval and adult stages of the susceptible parasites, the glycogen stores of the parasites are depleted. Degenerative changes in the endoplasmic reticulum, the mitochondria of the germinal layer, and the subsequent release of lysosomes result in decreased production of adenosine triphosphate (ATP), which is the energy required for the survival of the helminth.

Dosage

A1 dosage

To keep animal free from helminths animal should be treated at 3 months interval.

Cattle & Buffalo: 7.5-10 mg/kg body weight or 14 bolus for 30-40 kg body weight, 12 bolus for 60-80 kg body weight & 1 boli for 120-160 kg body weight.

Goat & Sheep: 5-7.5 mg/kg body weight or 112 bolus for 13-20 kg body weight & 1 6 bolus for 27-40 kg body weight.

Dog & Cat: 15 mg/kg body weight or 18 bolus for 8-10 kg body weight & 14 bolus for 16-20 kg body weight.

Or as directed by the registered Veterinarian.

Side Effects

A1 is time tested and clinically proven well tolerated drug. Established wide safety margin than any other anthelmentic due to greater selective affinity for parasitic b-tubulin than for animal tissues. However, in some cases nausea and vomiting may occur.

Toxicity

Symptoms of overdose include elevated liver enzymes, headaches, hair loss, low levels of white blood cells (neutropenia), fever, and itching.

Precaution

Before using A1 inform the registered Veterinarian that your animals are not allergic to it; or to other benzimidazole anthelmintic drugs (e.g. Mebendazole).

Interaction

A1 has been shown to induce liver enzymes of the cytochrome P-450 system responsible for its own metabolism. There is, therefore, a theoretical risk of interaction with theophylline, anticonvulsants, anticoagulants, oral contraceptives and oral hypoglycaemics. Care should therefore be exercised during the introduction of A1 in patients receiving the above groups of compounds

Food Interaction

• Take with a high fat meal. A high fat meal increases solubility and absorption. Take with food when treating systemic infections.

[Moderate] ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of albendazole, which is rapidly converted by hepatocytes and intestinal mucosal cells into the active metabolite, albendazole sulfoxide (ABZSX), following absorption.

The proposed mechanism is stimulation of gastric acid secretion, as the absorption of albendazole is thought to be pH-dependent.

According to the product labeling, plasma concentrations of ABZSX are up to 5-fold higher on average when albendazole is administered with a fatty meal (fat content approximately 40 g) compared to administration in the fasted state.

In one study of six healthy male volunteers, administration of a single 10 mg

The elimination half-life was not affected.
br> MONITOR: Grapefruit juice may increase the oral bioavailability of albendazole, which is rapidly converted by hepatocytes and intestinal mucosal cells into the active metabolite, albendazole sulfoxide (ABZSX), following absorption.

The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit.

In six healthy male volunteers, administration of a single 10 mg

However, because pharmacokinetic interactions involving grapefruit juice are often subject to a high degree of interpatient variability, the extent to which a given patient may be affected is difficult to predict.

MANAGEMENT: To ensure maximal oral absorption, albendazole should be taken with food.

Grapefruit juice may also enhance the oral bioavailability of albendazole.

A1 Drug Interaction

Unknown: aspirin, aspirin, amoxicillin, amoxicillin, amoxicillin / clavulanate, amoxicillin / clavulanate, ciprofloxacin, ciprofloxacin, acetaminophen, acetaminophen, valproic acid, valproic acid, multivitamin, multivitamin, cyanocobalamin, cyanocobalamin, ascorbic acid, ascorbic acid, cholecalciferol, cholecalciferol

A1 Disease Interaction

Major: myelosuppressionModerate: hepatobiliary dysfunction, neurologic dysfunction, renal impairment

Elimination Route

Poorly absorbed from the gastrointestinal tract due to its low aqueous solubility. Oral bioavailability appears to be enhanced when coadministered with a fatty meal (estimated fat content 40 g)

Half Life

Terminal elimination half-life ranges from 8 to 12 hours (single dose, 400mg).

Elimination Route

A1 is rapidly converted in the liver to the primary metabolite, albendazole sulfoxide, which is further metabolized to albendazole sulfone and other primary oxidative metabolites that have been identified in human urine. Urinary excretion of albendazole sulfoxide is a minor elimination pathway with less than 1% of the dose recovered in the urine. Biliary elimination presumably accounts for a portion of the elimination as evidenced by biliary concentrations of albendazole sulfoxide similar to those achieved in plasma.

Pregnancy & Breastfeeding use

A1 should not use first 45 days of pregnancy of cow. Do not administer to ewes or does during the first 30 days of pregnancy. Sufficient data on use during lactation is not available. Therefore breast feeding should be discontinued during and for a minimum of 5 days after treatment.

Contraindication

This is known to be teratogenic and embryo-toxic in some animals. Therefore it should not be administered during pregnancy or in women thought to be pregnant. It should only be used in the treatment of echinococcosis if there is constant medical supervision with regular monitoring of serumtransaminase concentrations and of leucocyte and platelet counts.

Acute Overdose

If poisoning or excessive overdosageis suspected, it is recommended for vomiting be induction or gastric lavage and such symptomatic supportive therapy to be administered.

Interaction with other Medicine

Cimetidine, Praziquantel and Dexamethasone have been reported to increase the plasma levels of A1 active metabolite.

Storage Condition

Do not store above 30 degree centigrade. Keep away from light and out of the reach of children.

Innovators Monograph

You find simplified version here A1