Background: Negative symptoms are categorized by some of the scholars into ‘primary vs secondary ‘, ‘enduring vs transitory ‘and ‘treatment-resistant vs treatmentresponsive’ groups. But it seems that such kind of grouping may not be practically supportable.
Objective: Exploring the genuineness of the abovementioned grouping and reports regarding resistance of negative symptoms against current treatments.
Method: After a primary survey regarding the frequency of negative symptoms amongst two hundreds and seventy schizophrenic patients, by means of Scale for Assessment of Negative Symptoms (SANS), in three random, double-blind, clinical trials (RCTs), and based on definite inclusion and exclusion criteria, the effectiveness of different adjunctive drugs respecting improvement of negative symptoms had been assessed.
Results: the frequency of affecting blunting, alogia, avolition-apathy, anhedonia-asociality and attention deficit was %96.28, %94.80, %99.62, %98.88 and %99.25, respectively. Citalopram, alprazolam, and clomipramine in the first tryout, nortriptyline in the second study, and maprotiline in the third trial were significantly more efficacious then placebo. In 31.2%, 28%, 26.4%, 24%and 22.4% of the patients there was about 20% reduction in the severity of attention deficit, alogia, affective blunting, anhedonia- asociality and avolition-apathy, respectively.
Conclusion: Conventional classification of negative symptoms into above-mentioned groups may not be practically supportable. Also maybe it is better to consider them solely in the Criterion B of diagnostic criteria, which considers the level of functioning.