Kretschmer conducted a very detailed study of sensitive paranoia over a period of more than 30 years. His book “Der sensitive Beziehunswahn” published in 1950, and translated as “Paranoia and sensitivity” , described a large number of cases in very great detail. However, antidepressants and neuroleptics did not exist at the time of publication of this book. Their introduction in 1952 for the treatment of delusional disorder led to a revision of the basic concepts. Research psychiatrists have subsequently tried to determine which medications are able to most effectively stabilize sensitive paranoia.
A consensus appears to have been gradually reached in favour of a combination of an antidepressant at conventional doses with a low or medium dose of neuroleptic, as illustrated by the following quotations.
A. PROSPERI and G. PUPESCHI wrote : “Chemotherapy is generally mixed, using a combination of antidepressant and neuroleptics (Guyautat et al., 1966; Sutter et al., 1968). Antidepressants, preferably tricyclics or serotonin reuptake inhibitors, are prescribed according to the conventional dosages and durations. They must be initiated at the onset of the disorders.
Incisive neuroleptics, which are not systematically proposed by all authors, must be used at low to medium doses. At excessively high doses, by inhibiting the delusional symptoms, may worsen the depression. Atypical neuroleptics or antipsychotics could have an indication of choice in this setting, but always at low doses.”
Similarly, J.P. OLIE, T. GALLARDA, and E. DUAUX indicated : “Some sensitive paranoia subjects require long-term chemotherapy (Anafranil, 50 mg/day and Largactil, 100 mg/day)”. Note that the dose of the antidepressant Anafranil is classical, while a low dose of the neuroleptic Largactil is recommended.
A. FOURNIER  wrote: “After 2 weeks of treatment of a patient with Kretschmer’s sensitive paranoia, essentially comprising neuroleptics (Haloperidol and Nozinan), the clinical features remained unchanged and the delusions persisted. We added treatment with Floxyfral at a dose of 150 mg per day (three 50 mg tablets) and, after a period of 10 to 15 days, a marked improvement was observed with lucid and critical insight into the delusions. This state allowed the patient to be discharged from hospital about one month after admission”
These authors emphasized the need for moderate doses of neuroleptics to avoid accentuating the depression.
This was confirmed by M. ESCANDE, L. GAYRAL, and E. GOLDBERGER : “A frequent reaction is the depressive reaction which accompanies the delusional state and which deteriorates during the course of treatment, when the delusional activity has been treated with a long-acting neuroleptic.” These same authors, in another paper , indicated that this depressive reaction is frequently accompanied by hypochondria.
M. ESCANDE and B. BONNET precisely explained the causes for this “depressive reaction” : “Depression in these cases is clearly related to clinical pharmacological effects, but are inseparable from the psycho-structural modifications, including bereavement of delusions, perceived as a loss for the ideal self.”
This depression is often very difficult to characterize as such. Many authors use the term “masked depression”, as it is hidden by the delusions. However, it is really present and responds favourably to antidepressants.