How do you treat Angiostrongylus?: A Review of Medications and Therapeutic Strategies

October 6, 2025 •

3 min read

The parasite Angiostrongylus cantonensis, also known as the rat lungworm, is the most common infectious cause of eosinophilic meningitis, with thousands of cases reported globally. Deciding how do you treat Angiostrongylus is complex, involving symptomatic management and, in some cases, a combination of corticosteroids and anthelmintics. This article explores the current approaches to managing this multifaceted parasitic infection.

Quick Summary

Treatment for Angiostrongylus infection primarily focuses on supportive care and reducing inflammation, particularly for the meningitis caused by A. cantonensis. While anthelmintics like albendazole are sometimes used, their efficacy remains debated due to concerns about a potential immune response from dying parasites. Supportive measures often include corticosteroids and pain management, while A. costaricensis infections are generally self-limiting.

Key Points

Supportive Care is Primary for A. cantonensis: Treatment for rat lungworm disease (eosinophilic meningitis) focuses on managing symptoms with analgesics, repeated lumbar punctures for high intracranial pressure, and corticosteroids to reduce inflammation.
Corticosteroids Reduce Headaches: High-dose corticosteroids, such as prednisolone, have been shown to significantly reduce the duration of severe headaches associated with Angiostrongylus cantonensis meningitis.
Anthelmintic Use is Still Debated: While once discouraged due to fears of an inflammatory response from dying larvae, anthelmintic drugs like albendazole are now considered beneficial by some guidelines, particularly when used early and in combination with steroids.
Combination Therapy with Albendazole: When anthelmintics are used, they are typically co-administered with corticosteroids to blunt the inflammatory reaction caused by the parasites' death.
A. costaricensis is Self-Limiting: Infections with Angiostrongylus costaricensis, which cause abdominal illness, usually resolve spontaneously and do not have a specific proven treatment.
Prevention is Key: The most effective strategy is prevention, which involves avoiding the consumption of raw or undercooked slugs, snails, and crustaceans, and to thoroughly wash fresh produce.
Long-term Sequelae are Possible: Severe neuroangiostrongyliasis can lead to long-term neurological complications such as chronic pain, fatigue, and nerve deficits, requiring ongoing management with a multidisciplinary team.

Understanding the Distinct Clinical Syndromes

Treatment strategies for angiostrongyliasis differ significantly depending on the species of the parasite and the affected area of the body. The two species that most commonly cause human disease are Angiostrongylus cantonensis and Angiostrongylus costaricensis. A. cantonensis primarily affects the central nervous system (CNS), causing eosinophilic meningitis, while A. costaricensis mainly causes intestinal inflammation known as eosinophilic enteritis.

How Angiostrongylus cantonensis (Rat Lungworm) is Treated

Neuroangiostrongyliasis, caused by A. cantonensis, is a complex condition to manage. Treatment is largely supportive, aiming to alleviate the severe headache and other neurological symptoms caused by the inflammatory response to the migrating larvae. The larvae eventually die in the CNS because humans are not their definitive hosts.

Corticosteroids for Neuroinflammation

High-dose corticosteroids are a cornerstone of treatment for eosinophilic meningitis caused by A. cantonensis. These medications, such as prednisolone and dexamethasone, work by suppressing the inflammatory reaction in the CNS caused by the parasite larvae. A randomized controlled trial showed that corticosteroids reduced the duration of headaches and the need for repeated lumbar punctures. Early administration is recommended.

The Controversial Role of Anthelmintics

The use of anthelmintic drugs like albendazole to kill A. cantonensis larvae has been controversial due to concerns about an exaggerated inflammatory response from dying parasites. However, some guidelines, particularly from endemic areas, now suggest that albendazole may be beneficial, especially when given early and with corticosteroids. One study indicated that albendazole with dexamethasone was effective in a mouse model.

Managing Intracranial Pressure

Therapeutic lumbar punctures can help relieve severe headaches caused by high intracranial pressure. Corticosteroids can also decrease the need for repeated punctures.

Supportive and Long-Term Care

Supportive care includes analgesics for pain, anti-nausea medications, and consultation for chronic neurological issues. Physical and occupational therapy may also be necessary.

Treatment for Angiostrongylus costaricensis (Abdominal Angiostrongyliasis)

Infections with A. costaricensis typically resolve on their own without specific anthelmintic treatment. Treatment focuses on managing symptoms like abdominal pain and nausea. In rare cases, surgery may be needed for severe intestinal inflammation. Anthelmintics are not proven effective for this species and might worsen the condition.

Comparison of Angiostrongylus Treatment Strategies

This table summarizes the different approaches for treating infections caused by the two primary Angiostrongylus species affecting humans.


Feature	Angiostrongylus cantonensis	Angiostrongylus costaricensis
Primary Manifestation	Eosinophilic meningitis	Eosinophilic enteritis
Larval Destination	Central Nervous System (CNS)	Intestinal wall
Primary Treatment Goal	Reduce neuroinflammation, manage symptoms	Symptom management
Role of Corticosteroids	Standard of care to reduce inflammation and headache	Generally not indicated, as intestinal inflammation is usually self-limiting
Role of Anthelmintics	Controversial but increasingly considered with corticosteroids	Not effective; may worsen condition
Lumbar Puncture	Used therapeutically to relieve high intracranial pressure and headache	Not relevant for intestinal infection
Surgical Intervention	Generally not required, except for rare ocular cases	May be necessary for severe intestinal inflammation or complications like obstruction
Prognosis	Most recover completely, but severe cases can have long-term neurological sequelae	Most infections resolve spontaneously

Future Directions and Research

More research, including randomized controlled trials, is needed to clarify the role of anthelmintics in neuroangiostrongyliasis. There is also ongoing research into better diagnostic methods and novel therapies.

Public Health Awareness and Prevention

Prevention is crucial and involves avoiding raw or undercooked slugs, snails, and contaminated produce, as recommended by the CDC. Education on food safety is key.

Conclusion

Treating Angiostrongylus depends on the species. For A. cantonensis, treatment focuses on corticosteroids to manage inflammation, with the cautious use of anthelmintics like albendazole also being considered. For A. costaricensis, supportive care is the primary approach as the infection is usually self-limiting. Continued research is essential to improve treatment strategies.

Frequently Asked Questions

There is no single 'cure' for rat lungworm disease (Angiostrongylus cantonensis). The larvae eventually die in the human host, but treatment focuses on managing the symptoms caused by the body's inflammatory response to the parasite. This includes using corticosteroids and supportive care.

The main medication used to treat the inflammatory symptoms of Angiostrongylus cantonensis meningitis is corticosteroids (like prednisolone). The use of anthelmintics (like albendazole) is sometimes added but remains controversial and requires careful consideration.

Anthelmintics have historically been controversial because killing a large number of parasites simultaneously might cause an intense inflammatory response as their antigens are released. This could potentially worsen neurological symptoms. For this reason, if used, anthelmintics are often paired with anti-inflammatory corticosteroids.

Infections with Angiostrongylus costaricensis, the abdominal form, are typically managed with supportive care. The illness is usually self-limiting and resolves on its own. Anthelmintics are not considered effective for this species and may be harmful.

Corticosteroid treatment can have side effects, particularly with long-term use. These may include hyperglycemia, weight gain, and immunosuppression. Anthelmintics are generally safe but require monitoring.

Yes, especially with severe neuroangiostrongyliasis. Potential long-term sequelae can include chronic neuropathic pain, limb weakness, fatigue, and persistent headaches, requiring ongoing management with a multidisciplinary team.

There is no widely established preventative medication for Angiostrongylus infection. The most effective prevention is to avoid eating raw or undercooked slugs, snails, and crustaceans, and to thoroughly wash fresh produce.