What is the treatment for a parasitic infection causing a rash and gastrointestinal (GI) upset?

From the Guidelines

Treatment for a parasitic infection causing rash and gastrointestinal upset should involve albendazole 400 mg daily for 3 days, as recommended by the most recent guidelines. This approach is based on the latest evidence from the UK guidelines for the investigation and management of eosinophilia in returning travellers and migrants, published in 2025 1. The guidelines specifically address hookworm infection, which can cause a maculopapular rash, nausea, vomiting, diarrhea, and abdominal pain.

Key Considerations

• The prepatent period for hookworm infection is 5–9 weeks, and the mode of transmission is through larvae penetrating the skin or oral acquisition 1.
• Clinical presentation may include a transient itch, maculopapular rash, and gastrointestinal symptoms such as nausea, vomiting, diarrhea, and abdominal pain 1.
• Investigations should include concentrated stool microscopy or faecal PCR to confirm the diagnosis.
• In severe cases, prednisolone 40-60 mg once daily may be suggested, and specialist advice should be sought, as management in an intensive care setting may be needed 1.

Treatment Approach

• Albendazole 400 mg daily for 3 days is the recommended treatment for hookworm infection 1.
• Supportive care, including oral rehydration for diarrhea and antihistamines for itching, may help manage symptoms.
• Proper handwashing, food hygiene, and avoiding contaminated water sources are essential to prevent reinfection.

Comparison with Other Options

• While other antiparasitic medications like mebendazole or ivermectin may be effective for other types of parasitic infections, such as ascariasis 1, albendazole is specifically recommended for hookworm infection.
• The treatment approach should be tailored to the specific pathogen and clinical presentation, and consultation with an infectious disease specialist is advisable for systemic parasitic infections.

From the FDA Drug Label

Metronidazole tablets are indicated in the treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess. Ivermectin is active against various life-cycle stages of many but not all nematodes. It is active against the tissue microfilariae of Onchocerca volvulus but not against the adult form. Its activity against Strongyloides stercoralis is limited to the intestinal stages

The treatment for a parasitic infection causing rash and GI upset may be ivermectin or metronidazole, depending on the specific parasite causing the infection.

• Ivermectin is effective against certain nematodes, such as Strongyloides stercoralis and Onchocerca volvulus.
• Metronidazole is effective against amebiasis, which can cause GI upset and other symptoms. However, the choice of treatment should be based on the specific diagnosis and medical evaluation of the patient 2 3.

From the Research

Treatment Options

• Albendazole and mebendazole are broad-spectrum anthelmintics that can be used to treat parasitic infections, including those that cause rash and GI upset 4.
• These drugs work by blocking the microtubule systems of parasites, leading to inhibition of glucose uptake and transport, and ultimately cell death.
• Albendazole is also used to treat filarial infections, alone or in combination with other drugs, such as ivermectin or diethylcarbamazine 4.

Efficacy and Safety

• A study compared the efficacy and safety of albendazole plus ivermectin, albendazole plus mebendazole, albendazole plus oxantel pamoate, and mebendazole alone against Trichuris trichiura and concomitant soil-transmitted helminth infections 5.
• The results showed that albendazole plus oxantel pamoate was the most effective treatment, with a cure rate of 68.5% and an egg reduction of 99.2% 5.
• The study also found that about a fifth of the children reported adverse events, which were mainly mild, with abdominal cramps and headache being the most common 5.

Skin Manifestations

• Parasitic infections can cause skin manifestations, including rash and hives, due to the deposition of parasites into the perianal region 6.
• A study found that Ascaris lumbricoides was the most frequently implicated parasite in skin allergic manifestations, with acute angioedema or chronic rash being the major skin manifestations 7.
• The study also found that the atopic trait had no importance in the appearance of allergic manifestations in parasitic infestation 7.

Gastrointestinal Upset

• Parasitic infections of the gastrointestinal tract are a major cause of morbidity and mortality worldwide 8.
• The infections can cause a range of symptoms, including diarrhea, abdominal pain, and weight loss 8.
• Treatment of the underlying parasitic infection is essential to alleviate gastrointestinal upset 8.