From the Research
Dosage of Trimethoprim for Neurotoxoplasmosis
The dosage of Trimethoprim (TMP) for neurotoxoplasmosis is not explicitly stated in the provided studies as a single, universally accepted value. However, various studies suggest different dosages and combinations with sulfamethoxazole (SMX) for the treatment and prophylaxis of toxoplasmosis.
- In the study 1, patients with AIDS and toxoplasmic encephalitis were treated with TMP (10 mg/kg of body weight/day) and SMX (50 mg/kg/day) as acute therapy.
- The study 2 found that when used in combination, TMP (60 mg/kg per day) and SMX (300 mg/kg per day) protected all mice and gave a 'cure' in some cases in a murine model of toxoplasmosis.
- Another study 3 examined altered TMP-SMX ratios for prophylaxis and treatment of Toxoplasma gondii and Pneumocystis carinii dual infections in a rat model, suggesting that for prophylaxis, increasing the TMP dose to 100 mg/kg while reducing SMX to 5 or 20 mg/kg could be effective against toxoplasmosis.
- The study 4 discusses the effect of TMP and SMX on Toxoplasma gondii in vitro and in vivo, noting that in vivo, TMP fed by gavage or mixed in the diet had no effect in murine toxoplasmosis at doses as high as 200 mg/kg a day, but the combination of 200 mg/kg TMP-200 mg/kg SMX protected 87% of mice when administered by gavage.
Key Findings
- The combination of TMP and SMX is commonly used for the prevention of cerebral toxoplasmosis, with studies suggesting various dosages and ratios for treatment and prophylaxis 2, 1, 3.
- The efficacy of TMP alone or in combination with SMX can vary depending on the model used (in vitro, in vivo, murine, or human) and the specific dosages administered 4, 2, 1, 3.
- There is evidence to suggest that altering the TMP-SMX ratio, particularly increasing TMP while decreasing SMX, may be effective for prophylaxis against toxoplasmosis, especially in settings where sulfonamide intolerance is a concern 3.