From the Guidelines
Giardia infection typically presents with symptoms of diarrhea, bloating, and abdominal pain, similar to functional diarrhea or diarrhea-predominant irritable bowel syndrome, and can last for 2-6 weeks if untreated. According to the AGA technical review on the evaluation of functional diarrhea and diarrhea-predominant irritable bowel syndrome in adults 1, the symptoms of giardia infection can be similar to those of other gastrointestinal disorders, making diagnosis challenging.
Key Symptoms
- Diarrhea
- Bloating
- Abdominal pain These symptoms can be accompanied by other gastrointestinal issues, such as excessive gas and stomach gurgling. The infection can also lead to weight loss due to malabsorption of nutrients 1.
Diagnosis and Treatment
Diagnosis of giardia infection typically requires stool sample analysis, and treatment usually involves antiparasitic medications. The Centers for Disease Control and Prevention guidelines suggest testing three stools for ova and parasite examination, with further molecular testing of stools when these are negative but suspicion is still high 1.
Prevention
Preventive measures include thorough handwashing, drinking treated water, and avoiding swallowing water while swimming in potentially contaminated sources. Individuals at high risk of giardia infection, such as those exposed to contaminated water or those in endemic areas, should take extra precautions to prevent infection 1.
From the Research
Symptoms of Giardia
- Giardiasis infection may be asymptomatic, or can cause:
- The symptoms of giardiasis can vary in severity and duration, and may be affected by the treatment used 3, 4, 5, 6
Treatment Options
- Metronidazole is a commonly used treatment for giardiasis, but it may have side effects and require multiple doses 2, 3, 4, 5
- Tinidazole is a highly effective treatment for giardiasis, and can be administered as a single dose 3, 4, 6
- Albendazole is also used to treat giardiasis, but its efficacy may be lower than that of tinidazole 2, 4, 6
- Nitazoxanide is a new drug that has been developed for treating giardiasis, and has shown promise in clinical trials 4, 5
Efficacy of Treatments
- Tinidazole has been shown to be more effective than metronidazole and albendazole in treating giardiasis 4, 6
- Albendazole may have fewer side effects than metronidazole, but its efficacy may be lower 2
- The choice of treatment for giardiasis may depend on the severity of symptoms, the presence of side effects, and the availability of treatments 3, 4, 5, 6