
Medicine overview
Indications of Etrax
Etrax is an anthelmintic (antiparasitic) medicine used for the treatment of intestinal worm (helminth) infections.
Established/Approved Uses
- Ascariasis (roundworm infection caused by Ascaris lumbricoides) — this is the primary and most well-established indication for Etrax.
- Hookworm infection (Ancylostoma duodenale and Necator americanus), particularly light to moderate infections; Etrax is less effective against heavy hookworm burden and severe infections may need a repeat dose or an alternative anthelmintic.
Other Reported Uses (Variable Evidence)
- Infections with Enterobius vermicularis (threadworm/pinworm), Trichuris trichiura (whipworm), Strongyloides stercoralis, and Trichostrongylus species have been reported to respond to Etrax, though efficacy against these organisms is generally lower and less consistent than against ascariasis.
Historical/Discontinued Use — Not a Current Indication
Etrax was formerly used at low doses as an immunomodulatory adjunct to chemotherapy (fluorouracil) in colon cancer, and it has also been used in veterinary medicine. These uses have been withdrawn/discontinued in human medicine in many countries, including removal of the cancer-adjunct product from the market, because of the risk of serious agranulocytosis. Etrax is not recommended and should not be used for these purposes; its current, marketed human use is as an anthelmintic for intestinal worm infection.
Composition
Each tablet/capsule of Levamisole typically contains Levamisole hydrochloride equivalent to 40 mg or 50 mg of Levamisole base (strength varies by manufacturer). Levamisole is also available as an oral suspension/syrup, typically containing Levamisole hydrochloride equivalent to 40 mg of Levamisole base per 5 mL. Please check the product label of the specific brand dispensed, as exact strength and inactive ingredients vary by manufacturer.
Description
Etrax is a synthetic imidazothiazole derivative used as an anthelmintic (antiparasitic) agent. It is the pharmacologically active levo-isomer of tetramisole.
Etrax acts by paralyzing susceptible nematode (roundworm) parasites through depolarizing neuromuscular blockade, which causes the worms to detach from the intestinal wall and be expelled from the body in the stool by normal gut motility, usually within 24 hours of dosing.
Etrax is administered orally, usually as a single dose, and is well absorbed from the gastrointestinal tract.
Therapeutic Class
Etrax belongs to the anthelmintic (antiparasitic) class of drugs, specifically the imidazothiazole group of anthelmintics.
Pharmacology
Levamisole is the active levo-isomer of tetramisole. Its primary anthelmintic action is due to a depolarizing, ganglion-stimulant type neuromuscular blocking effect on susceptible nematodes, which causes irreversible paralysis of the worm's musculature.
Once paralyzed, the worms lose their grip on the intestinal wall and are expelled from the gastrointestinal tract by normal peristalsis, largely intact, generally within 24 hours.
Levamisole also has immunomodulatory properties — it can restore depressed immune function (particularly T-cell mediated responses) — but this action is not the basis for its current approved anthelmintic use and low-dose immunomodulatory use has been discontinued in human medicine due to safety concerns (see Precautions and Warnings).
Pharmacokinetics: Levamisole is rapidly and well absorbed after oral administration, with peak plasma concentrations reached in 1.5–2 hours. It is extensively metabolized in the liver, and metabolites are excreted mainly in the urine, with a plasma elimination half-life of approximately 3–4 hours.
Dosage & Administration of Etrax
Etrax is usually given as a single oral dose, preferably after a light meal.
| Age Group | Dose |
|---|---|
| 1–4 years | 1 tablet (40 mg) or 5 mL oral suspension, as a single dose |
| 5–15 years | 2 tablets (80 mg) or 10 mL oral suspension, as a single dose |
| 16 years and above (adults) | 3 tablets (120 mg) or 15 mL oral suspension, as a single dose |
For heavy or severe hookworm infection, a repeat dose of the same strength may be given one to seven days after the first dose, on a physician's advice.
Complete the course of Etrax exactly as prescribed. Do not repeat doses or use Etrax more frequently than advised by a physician, and do not share this medicine with others, since inappropriate or repeated dosing has been linked to serious blood-cell side effects (see Precautions and Warnings).
Stool examination may be repeated after 2–3 weeks in persistent or heavy infections to confirm clearance, on the physician's advice.
Administration of Etrax
Etrax is for oral use only.
- Take Etrax preferably after a light meal to reduce the chance of stomach upset.
- Swallow tablets whole with water; the oral suspension should be measured with an accurate measuring device (not a household spoon).
- Shake the oral suspension well before use.
- Etrax is usually given as a single dose; follow your physician's instructions regarding any repeat dosing.
- Avoid alcohol during and for a few days after taking Etrax (see Interactions).
Interaction of Etrax
The following clinically significant interactions have been reported with Etrax:
- Alcohol: Etrax can cause a disulfiram-like reaction (facial flushing, nausea, vomiting, palpitations) when alcohol is consumed during treatment. Avoid alcohol during and for a few days after taking Etrax.
- Phenytoin: Etrax may increase plasma levels of phenytoin, increasing the risk of phenytoin toxicity; monitor phenytoin levels/clinical status if co-administered.
- Warfarin and other coumarin anticoagulants: Etrax may potentiate the effect of warfarin, increasing bleeding risk; monitor coagulation parameters (e.g., INR) if used together.
- Other anthelmintics: Etrax has been reported to increase the bioavailability of ivermectin and to decrease the bioavailability of albendazole when co-administered; avoid combining anthelmintics unless specifically directed by a physician.
Always inform your physician or pharmacist about all medicines, supplements, and alcohol use before starting Etrax.
Contraindications
Levamisole is contraindicated in:
- Patients with known hypersensitivity to Levamisole or any component of the formulation.
Levamisole should not be used during pregnancy (see Pregnancy and Lactation for detailed guidance) and is not recommended for the historical low-dose immunomodulatory/chemotherapy-adjunct use because of the risk of serious agranulocytosis (see Precautions and Warnings).
Side Effects of Etrax
Side effects of Etrax are generally infrequent, mild, and transient when used at the recommended single anthelmintic dose.
Common Side Effects
- Nausea, vomiting
- Abdominal pain/cramps
- Dizziness (giddiness)
- Headache
- Metallic taste
- Diarrhea
Rare but Serious Side Effects
- Agranulocytosis — a serious drop in white blood cells that increases infection risk; this is rare with standard short-course anthelmintic dosing but is a well-documented, serious risk with repeated or prolonged use (see Precautions and Warnings).
- An encephalopathy-like syndrome (confusion, altered consciousness, seizures) occurring 2–3 weeks after treatment has been reported rarely.
- Skin rash or hypersensitivity reactions.
- Transient fever, particularly in patients with concurrent microfilaraemia.
Seek prompt medical attention for fever, sore throat, unusual bruising/bleeding, mouth ulcers, or signs of infection during or after taking Etrax, or for any severe or persistent symptoms.
Pregnancy & Lactation
Pregnancy: Etrax is generally not recommended during pregnancy. Although animal reproduction studies have not shown clear teratogenic effects, adequate and well-controlled studies in pregnant women are lacking. Etrax should be used in pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus; consult a physician before use.
Lactation: It is not well established whether Etrax passes into breast milk. Caution is advised, and Etrax should be used during breastfeeding only if clearly needed and under medical supervision, weighing the benefits of treatment against any potential risk to the nursing infant.
Precautions & Warnings
Agranulocytosis Risk
Serious agranulocytosis (a marked drop in a type of white blood cell, increasing susceptibility to infection) has been reported with Etrax, particularly with repeated dosing or prolonged/higher-dose use in its former immunomodulatory application; this led to withdrawal of Etrax for non-anthelmintic uses in several countries. Although this risk is much lower with the short, single-dose anthelmintic regimen, patients and caregivers should watch for fever, sore throat, mouth ulcers, unusual bruising or bleeding, or signs of infection during or shortly after treatment, and seek prompt medical attention if these occur. Do not repeat doses of Etrax more often than prescribed.
Neurological Effects
Rare cases of encephalopathy and, in the context of prolonged/repeated exposure (including illicit drug contamination scenarios not related to standard medical dosing), multifocal inflammatory leukoencephalopathy have been associated with Etrax. With standard short-course anthelmintic dosing, this risk appears very low, but caregivers should seek medical attention promptly if confusion, unusual movements, seizures, or altered consciousness occur after treatment.
Alcohol
Avoid alcohol during and for several days after taking Etrax, due to the risk of a disulfiram-like reaction.
Hepatic Impairment
Use with caution in patients with significant liver disease, as Etrax is extensively metabolized by the liver.
General
Complete the course of Etrax exactly as directed by the physician; do not use more frequently, in higher doses, or for longer than prescribed, and do not share this medicine with others without medical advice, as unsupervised repeated use increases the risk of serious blood-related side effects.
Overdose Effects of Etrax
Overdose of Etrax may cause exaggeration of its known side effects, such as nausea, vomiting, abdominal pain, dizziness, and headache; neurological symptoms (confusion, seizures) may occur with significant overdose.
There is no specific antidote for Etrax overdose. If overdose is suspected, seek immediate medical attention or contact a poison control center/emergency services. Treatment is supportive and symptomatic, based on medical assessment; do not attempt home treatment for a suspected overdose.
Storage Conditions
Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.
Use In Special Populations
Renal Impairment
No well-established dose adjustment is required for renal impairment; however, use with caution and under medical supervision in patients with significant renal disease.
Hepatic Impairment
Use with caution in patients with significant hepatic impairment, since Etrax is extensively metabolized by the liver; consult a physician for individualized dosing.
Elderly
No specific dose adjustment has been established for elderly patients; use the standard adult dose with routine clinical monitoring.
Immunocompromised Patients
Use with caution and close monitoring in patients with pre-existing blood disorders or immunosuppression, given the rare but serious risk of agranulocytosis associated with Etrax (see Precautions and Warnings).
Duration Of Treatment
Etrax is typically given as a single dose for standard intestinal worm infections. For heavy or persistent hookworm infection, a physician may advise a single repeat dose 1–7 days after the first dose. Etrax is not intended for continuous or long-term daily use; repeated courses, if needed, should only be taken on medical advice, spaced appropriately, and should not be self-directed by the patient.
Drug Classes
Levamisole belongs to the imidazothiazole class of anthelmintic (antiparasitic) agents.
Mode Of Action
Levamisole, the active levo-isomer of tetramisole, causes depolarizing neuromuscular blockade in susceptible nematode parasites, leading to persistent muscular contraction and irreversible paralysis of the worm. The paralyzed worm can no longer maintain its grip on the intestinal mucosa and is expelled from the gastrointestinal tract by normal peristaltic movement, usually within 24 hours of dosing.
Pediatric Uses
Etrax is used in children for treatment of intestinal worm infections, with weight/age-based single dosing as outlined in Dosage and Administration:
- 1–4 years: 40 mg (1 tablet or 5 mL suspension) as a single dose.
- 5–15 years: 80 mg (2 tablets or 10 mL suspension) as a single dose.
Safety and efficacy of Etrax in children under 1 year of age have not been well established; use in this age group only if specifically advised by a physician after weighing benefits and risks. Caregivers should monitor children for fever, sore throat, or signs of infection after dosing, given the rare risk of agranulocytosis, and should not repeat doses without medical advice.
Frequently Asked Questions
Q: What is Etrax 40 mg Tablet used for?
A: Etrax 40 mg Tablet is an anthelmintic (antiparasitic) medicine used mainly to treat roundworm (ascariasis) infection, and it is also used for hookworm and certain other intestinal worm infections. It works by paralyzing the worms so they are expelled from the body in the stool.
Q: How is Etrax 40 mg Tablet taken?
A: Etrax 40 mg Tablet is usually taken as a single oral dose, preferably after a light meal. Dosing depends on age: 1 tablet (40 mg) or 5 mL syrup for ages 1–4 years, 2 tablets (80 mg) or 10 mL for ages 5–15 years, and 3 tablets (120 mg) or 15 mL for those 16 years and above. For severe hookworm infection, a physician may advise a repeat dose 1–7 days later.
Q: Can I drink alcohol while taking Etrax 40 mg Tablet?
A: No. Alcohol should be avoided during and for a few days after taking Etrax 40 mg Tablet, as it can cause a disulfiram-like reaction with symptoms such as facial flushing, nausea, vomiting, and palpitations.
Q: Is Etrax 40 mg Tablet safe during pregnancy?
A: Etrax 40 mg Tablet is generally not recommended during pregnancy. It should be used only if clearly needed and if the potential benefit outweighs the potential risk to the fetus, and only under a physician's guidance. Adequate human studies are lacking, so caution is advised.
Q: What are the serious side effects of Etrax 40 mg Tablet I should watch for?
A: Although uncommon with standard single-dose use, Etrax 40 mg Tablet has been associated with a serious drop in white blood cells called agranulocytosis, especially with repeated or prolonged use. Watch for fever, sore throat, mouth ulcers, unusual bruising/bleeding, or signs of infection during or shortly after treatment, and seek medical attention promptly if these occur. Rarely, neurological symptoms such as confusion or seizures occurring weeks after treatment have been reported; seek medical care if these occur.
Q: Can Etrax 40 mg Tablet be repeated if the worm infection does not clear?
A: Do not repeat Etrax 40 mg Tablet on your own. If symptoms persist or a stool test shows ongoing infection, consult your physician, who may advise a supervised repeat dose or an alternative anthelmintic, since unsupervised repeated dosing increases the risk of serious blood-related side effects.
Disclaimer
The information provided is accurate to the best of our knowledge, but it does not replace professional medical advice. We cannot guarantee its completeness or accuracy, and the absence of specific information about a drug should not be taken as an endorsement. We are not responsible for any consequences arising from this information, so please consult a healthcare professional for any concerns or questions.