No empiric regimen consisting solely of oral agents is recommended, even in the later stages of therapy. Folinic acid 10mg daily is given to decrease bone marrow suppression from pyrimethamine. Sulfadiazine is given in a dose of 1 gram orally every 6 hours. The limitation of empiric therapy is that radiologic distinction between toxoplasmosis and other lesions is not accurate. Progressive deterioration, an atypical CT or MRI, or failure to show clinical and imaging improvement during 2 weeks of anti-toxoplasma therapy, generally prompts biopsy or aspiration.
Some clinicians also use a negative toxoplasma serology to prompt early neurosurgical intervention.
Patients taking cotrimoxazole prophylaxis for pneumocytosis may be at a lower risk for toxoplasmosis and are therefore more likely to have an alternative diagnosis. The range of aetiologic agents for brain abscess is so broad in these patients that empiric therapy has limited value. Early neurosurgical intervention is usually indicated together with culture and biopsy of the lesion. Corticosteroids may be lifesaving in certain settings, including when there is rapid neurologic deterioration associated with an increase in intracranial pressure. The introduction of improved imaging studies and stereotactic guided aspiration has made a dramatic impact on the outcome in patients with brain abscesses.