From the Guidelines
Treatment for giardia typically involves antiparasitic medications, with tinidazole being the first choice, as recommended by the 2017 Infectious Diseases Society of America clinical practice guidelines 1.
Recommended Treatment Options
- Tinidazole is approved in the United States for children aged ≥3 years and is available in tablets that can be crushed.
- Metronidazole is an alternative option, but it has a high frequency of gastrointestinal side effects.
- A pediatric suspension of metronidazole is not commercially available but can be compounded from tablets.
Important Considerations
- Patients should stay well-hydrated and may benefit from a bland diet to reduce gastrointestinal symptoms.
- Good hygiene practices, including thorough handwashing after using the bathroom and before handling food, are essential to prevent reinfection and transmission to others.
- It's essential to complete the full course of medication even if symptoms improve before finishing treatment.
Dosage and Administration
- Tinidazole: single 2-gram dose for adults, with dosage adjusted based on weight for children.
- Metronidazole: 250 mg three times daily for 5-7 days for adults, with dosage adjusted based on weight for children.
Evidence-Based Recommendation
The recommendation for tinidazole as the first choice for treating giardia is based on the most recent and highest quality study available, which is the 2017 Infectious Diseases Society of America clinical practice guidelines 1. This guideline provides the most up-to-date and evidence-based recommendations for the treatment of giardia, prioritizing morbidity, mortality, and quality of life as the outcome.
From the FDA Drug Label
1.2 Giardiasis Tinidazole is indicated for the treatment of giardiasis caused by Giardia duodenalis (also termed G. lamblia) in both adults and pediatric patients older than three years of age [see Clinical Studies ( 14.2)] . INDICATIONS AND USAGE ALINIA is an antiprotozoal indicated for the treatment of diarrhea caused by Giardia lamblia or Cryptosporidium parvum(1).
Treatment for Giardia:
- Tinidazole is indicated for the treatment of giardiasis caused by Giardia duodenalis in adults and pediatric patients older than three years of age 2.
- Nitazoxanide (ALINIA) is an antiprotozoal indicated for the treatment of diarrhea caused by Giardia lamblia 3. Key points:
- Tinidazole and nitazoxanide are both effective treatments for giardiasis.
- The choice of treatment may depend on the patient's age, medical history, and other factors.
From the Research
Treatment Options for Giardia
- The first-line drug treatment for giardiasis is tinidazole, which requires only a single dose to cure infection in most individuals 4.
- Metronidazole is also effective, but it requires 5 to 7 days of three times a day therapy 4, 5.
- Nitazoxanide appears to be as effective as tinidazole or metronidazole, and it does not have the bitter taste of nitroimidazoles 4.
- Paromomycin is a good alternate for use during pregnancy, as it is not systematically absorbed 4, 5.
- Albendazole may be of similar effectiveness to metronidazole, may have fewer side effects, and has the advantage of a simplified regimen 6.
- Tinidazole was associated with higher parasitological cure than metronidazole and albendazole, and is considered the most effective drug for treating giardiasis 7.
Efficacy and Side Effects
- The cure rate of giardiasis varies between 60% and 100% with one course of treatment 4.
- Metronidazole can be expected to cure over 90% of individuals with a 5- to 7-day course 5.
- Tinidazole has a higher parasitological cure rate than metronidazole and albendazole 7.
- Albendazole probably has fewer side effects than metronidazole, including gastrointestinal and neurological side effects 6.
Alternative Treatments
- Quinacrine has excellent efficacy but may be poorly tolerated, especially in children 5.
- Furazolidone is an effective alternative but must be administered four times a day for 7 to 10 days 5.
- Nitazoxanide is effective against giardiasis but requires multiple doses 8.
- New potentially promising drug targets in Giardia have been identified, but there appears to be little activity toward clinical development of new drugs 8.