Parex
Parex Uses, Dosage, Side Effects, Food Interaction and all others data.
Parex is a synthetic derivative of benzimidazole with a potent anthelmintic activity against the most common nematodes and some cestodes. It is highly effective against ascariasis, enterobiasis, trichuriasis and hookworm infections. It is equally effective in single or in mixed infections. The effect of the drug is due to its ability to inhibit glucose uptake irreversibly but it does not affect blood glucose concentration in the host, even in high doses. Parex does not necessitate any dosage calculation since the same dosage is used for children and adults. It can be taken at any time and no special procedures such as purging, use of laxatives and/or dietary changes are required. Parasite immobilization and death occur slowly and clearance from the gastro-intestinal tract may not be completed up to 3 days after administration.
Parex is a (synthetic) broad-spectrum anthelmintic. The principal mode of action for Parex is by its inhibitory effect on tubulin polymerization which results in the loss of cytoplasmic microtubules.
| Trade Name | Parex |
| Availability | Prescription only |
| Generic | Mebendazole |
| Mebendazole Other Names | MBDZ, Mebendazol, Mébendazole, Mebendazole, Mebendazolum |
| Related Drugs | metronidazole, Flagyl, albendazole, nitazoxanide, praziquantel, piperazine, pyrantel, Albenza, Alinia |
| Weight | 500mg, 100mg |
| Type | Tablet |
| Formula | C16H13N3O3 |
| Weight | Average: 295.2927 Monoisotopic: 295.095691297 |
| Protein binding | 90-95% |
| Groups | Approved, Vet approved |
| Therapeutic Class | Anti-helminthic |
| Manufacturer | Innvotek Pharmaceuticals |
| Available Country | Pakistan |
| Last Updated: | September 19, 2023 at 7:00 am |
Uses
Parex is used for the treatment of pinworm (Enterobius vermicularis), round worm (Ascaris lumbricoides), hookworm (Ancylostoma duodenale and Necator americanus), whip worm (Trichuris trichiura), tape worm (Taenia solium and taenia saginata) and threadworm (Strongyloides stercoralis) in single or mixed infections
Parex is also used to associated treatment for these conditions: Ancylostoma caninum infection, Ancylostoma duodenale infection, Ascaris lumbricoides infection, Capillariasis, Enterobius vermicularis infection, Filariasis, Giardiasis, Necatoriasis due to necator americanus, Strongyloides Stercoralis Infection, Taenia solium infection, Toxocariasis, Whipworm infection
How Parex works
Parex causes degenerative alterations in the tegument and intestinal cells of the worm by binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization or assembly into microtubules. The loss of the cytoplasmic microtubules leads to impaired uptake of glucose by the larval and adult stages of the susceptible parasites, and depletes their glycogen stores. 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. Due to diminished energy production, the parasite is immobilized and eventually dies.
Dosage
Parex dosage
Parex 100 mg tablet and suspension: This have the same dosage schedule applies to adults & children.
Enterobiasis: A single tablet or 1 teaspoonful of the suspension.
Ascariasis, Ancylostomiasis, Trichuriasis: 2 tablets, one in the morning, the other in the afternoon for 3 consecutive days or 1 teaspoonful in the morning & 1 teaspoonful in the afternoon for 3 consecutive days
Taeniasis & strongyloidiasis:
- Adults: 2 tablets twice daily for 3 consecutive days.
- Children: 1 tablet twice daily or 1 teaspoonful twice daily for 3 consecutive days.
Parex 500 mg tablet: One Parex 500 mg tablet in a single intake regardless of body weight, for all nematode and some cestode infestations. The same dosage applies to adults and children age two years and above.
May be taken with or without food.
Side Effects
Parex is well tolerated by adults and children. It has virtually no side effects. Transient abdominal pain and diarrhoea have been reported only rarely, in case of massive infestation and expulsion of worms.
Toxicity
Acute oral toxicity (LD50): 620 mg/kg [Mouse]. Symptoms of overdose include elevated liver enzymes, headaches, hair loss, low levels of white blood cells (neutropenia), fever, and itching.
Precaution
Hepatic impairment. Children. Pregnancy and lactation.
Interaction
Concomitant treatment with cimetidine may inhibit the metabolism of mebendazole in the liver, resulting in increased plasma concentrations of the drug especially during prolonged treatment.
Food Interaction
- Take with or without food.
Parex Disease Interaction
Elimination Route
Poorly absorbed (approximately 5 to 10%) from gastrointestinal tract. Fatty food increases absorption.
Half Life
2.5 to 5.5 hours (range 2.5 to 9 hours) in patients with normal hepatic function. Approximately 35 hours in patients with impaired hepatic function (cholestasis).
Elimination Route
In man, approximately 2% of administered mebendazole is excreted in urine and the remainder in the feces as unchanged drug or a primary metabolite.
Pregnancy & Breastfeeding use
Parex should not be administered during pregnancy and in women thought to be pregnant. It is not known whether mebendazole or its metabolites are secreted in human breast milk. Thus Parex should not be used during lactation unless the potential benefits are considered to outweigh the potential risk associated with treatment.
Contraindication
Parex is contraindicated in pregnancy and in patients who have shown hypersensitivity to the product or any of its components.
Acute Overdose
Symptoms: Alopecia, reversible liver function disturbances, hepatitis, agranulocytosis, neutropenia, glomerulonephritis, abdominal cramps, nausea, vomiting and diarrhoea.
Management: Within the 1st hr after ingestion, gastric lavage may be performed. Activated charcoal may be given if considered appropriate.
Storage Condition
Store between 20-25° C.
Innovators Monograph
You find simplified version here Parex
Parex contains Mebendazole see full prescribing information from innovator Parex Monograph, Parex MSDS, Parex FDA label
FAQ
What is Parex used for?
Parex is a medication used to treat a number of parasitic worm infestations. This includes ascariasis, pinworm infection, guinea worm infections, hydatid disease, and giardia, among others. Parex also is used to treat: Common roundworms (ascariasis), Hookworms (ancylostomiasis, necatoriasis, uncinariasis).
How safe is Parex?
Parex generally safe. Taking an extra dose of Parex by accident is unlikely to cause any harm.
How does Parex work?
Parex works by stopping the worms using sugar (glucose).
What are the common side effects of Parex?
Common side effects of Parex are include;
- diarrhea.
- stomach pain, discomfort, or swelling.
- nausea.
- vomiting.
- loss of appetite.
Is Parex safe during pregnancy?
Parex are well tolerated, with no adverse events in pregnant women and their fetuses when given after the first trimester of pregnancy.
Is Parex safe during breastfeeding?
Parex use during lactation is considered to be safe due to a low oral absorption and unlikely excretion in milk.
Can I drink alcohol with Parex ?
Yes, you can drink alcohol with Parex.
When should be best taken of Parex?
Parex is best taken with meals, especially fatty ones (eg, meals that include whole milk or ice cream). This helps to clear up the infection by helping your body absorb the medicine better.
How many time can I take Parex daily?
Usually you need to take a dose 2 times a day for 3 days.
How long does Parex take to work?
Parex should start to work straight away but it may take several days to kill all the worms.
How long does Parex stay in my system?
The apparent elimination half-life after an oral dose ranges from 3 to 6 hours in most patients.
How long can I take Parex?
Parex is usually taken as a single dose, but it can be taken for around 3 days for some infections. The most common side effect is stomach pain.
Who should not take Parex?
Tell your doctor if you are pregnant or plan to become pregnant. Parex can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine. Parex is not approved for use by anyone younger than 2 years old.
What happens if I overdose?
Seek emergency medical attention. Overdose symptoms may include upper stomach pain, loss of appetite, dark urine, or jaundice (yellowing of the skin or eyes).
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
Can Parex cause liver damage?
Parex when given for prolonged periods in high doses has been associated with elevations in serum enzyme levels, and rare instances of acute, clinically apparent liver injury have been linked to its use.
