From the Guidelines
The treatment for Giardiasis (Giardia infection) is typically initiated with Tinidazole as the first-line treatment, with Metronidazole as an alternative option. According to the 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea 1, Tinidazole is the recommended first-choice treatment for Giardia lamblia infection. Some key points to consider when treating Giardiasis include:
- Tinidazole is approved in the United States for children aged ≥3 years and is available in tablets that can be crushed 1.
- Metronidazole has a high frequency of gastrointestinal side effects and is not FDA approved for the treatment of giardiasis, although it can be used as an alternative treatment option 1.
- The standard adult dosage for Tinidazole is typically a single dose of 2 grams, while the dosage for Metronidazole is 250 mg three times daily for 5-7 days, or alternatively 2 grams once daily for 3 days.
- For children, the recommended dose of Tinidazole is 50 mg/kg as a single dose, while the recommended dose of Metronidazole is 15 mg/kg/day divided into three doses for 5-7 days.
- During treatment, patients should maintain good hydration and may benefit from a bland diet to reduce gastrointestinal symptoms.
- Alcohol must be strictly avoided during treatment with Metronidazole or Tinidazole and for 48-72 hours afterward due to potential disulfiram-like reactions.
- Treatment success should be evaluated by resolution of symptoms, typically within 5-7 days after completing therapy, and no follow-up stool testing is needed if symptoms resolve.
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)] . 14. 2 Giardiasis Tinidazole (2 g single dose) use in giardiasis has been documented in 19 published reports from the world literature involving over 1,600 patients (adults and pediatric patients) In eight controlled studies involving a total of 619 subjects of whom 299 were given the 2 g × 1 day (50 mg/kg × 1 day in pediatric patients) oral dose of tinidazole, reported cure rates ranged from 80% (40/50) to 100% (15/15).
The treatment for Giardiasis (Giardia infection) is Tinidazole. The recommended dose is a single 2 g dose for adults, and 50 mg/kg × 1 day for pediatric patients 2.
From the Research
Treatment Options for Giardiasis
The treatment for Giardiasis typically involves the use of antimicrobial medications. The following are some of the commonly used treatment options:
- Tinidazole: a first-line drug treatment that requires only a single dose to cure infection in most individuals 3, 4, 5
- Metronidazole: an effective treatment that requires 5 to 7 days of three times a day therapy 3, 6, 7
- Nitazoxanide: appears to be as effective as tinidazole or metronidazole, with the added benefit of not having a bitter taste 3, 7
- Paromomycin: a good alternate for use during pregnancy 3, 6
- Albendazole: may be equivalent to metronidazole in achieving parasitological cure, with fewer side effects 7
Efficacy of Treatment Options
Studies have compared the efficacy of different treatment options for Giardiasis:
- Tinidazole has been shown to be more effective than metronidazole and albendazole in achieving parasitological cure 5
- Albendazole may have fewer side effects than metronidazole, with a simplified regimen 7
- Single-dose tinidazole has been found to be the most effective treatment for Giardiasis in symptomatic and asymptomatic children and adults 5
Side Effects and Considerations
The following side effects and considerations should be taken into account when treating Giardiasis: