Effects of clonidine in schizophrenic patients with primary polydipsia: three single case studies

Non-antipsychotic pharmacotherapy of psychogenic polydipsia: A systematic review

OBJECTIVE

Polydipsia is defined at the intake of excessive fluid (>3 L daily). Psychogenic polydipsia (PPD) presents without an identifiable medical cause and is often seen in patients with diagnoses of schizophrenia, OCD, anxiety, alcohol use disorder, and other psychotic disorders. The purpose of this systematic review is to assess the therapeutic effect of various non-antipsychotic medications on patients with a stable psychotic illness and concurrent PPD.

METHODS

A systematic search was conducted using the following databases: PubMed, MEDLINE with Full Text, CINAHL complete, Cochrane database of systematic reviews, Cochrane methodology register, MasterFILE Premier, APA PsychArticles, APA PsychInfo, APA PsycBooks, APA PsycTests, TRIP, Nursing and Allied Health. The quality of each retained study was assessed using appropriate risk of bias tools based on study design.

RESULTS

The initial search resulted in 1422 articles from which 22 articles were included for qualitative synthesis. Study designs ranged from case reports to double blind, placebo controlled randomized trials and was interpreted uniquely based on study design. Acetazolamide was effective in improving some PPD outcomes. Fluoxetine at high doses was effective in reducing fluid intake and polydipsia. Other medications included in this review performed equivocally for reduction of numerous parameters evaluating PPD.

CONCLUSION

No one drug appeared to be the most efficacious; however, some did show promise in specific populations. Those in need of pharmacotherapeutic options for PPD may consider one of the included agents to assist with co-morbid state. Further high-quality research is needed to provide better treatment guidance for PPD.

Do psychoactive drugs have a therapeutic role in compulsivity? Studies on schedule-induced polydipsia

RATIONALE

Clinical studies have shown that some psychoactive recreational drugs have therapeutic applications in anxiety, depression, and schizophrenia. However, to date, there are few studies on the therapeutic potential efficacy of recreational drugs in compulsive neuropsychiatric disorders.

OBJECTIVES

We explored the therapeutic potential of different psychoactive and psychedelic drugs in a preclinical model of compulsive behavior.

METHODS

Outbred male Wistar rats were selected as either high (HD) or low (LD) drinkers according to their behavior in schedule-induced polydipsia (SIP). Subsequently, we assessed the effects of acute administration of scopolamine (0.125, 0.25, and 0.5 mg/kg), methamphetamine (0.25, 0.5, 1.25, and 2.5 mg/kg), ketamine (1.25, 2.5, 5, and 10 mg/kg), cannabidiol (1 and 3 mg/kg), WIN21255-2 (0.5, 075, and 1 mg/kg), and AM404 (0.25 and 0.5 mg/kg) on compulsive drinking in SIP.

RESULTS

Scopolamine reduced dose-dependent compulsive drinking in HD compared with LD rats in SIP. Methamphetamine induced a dose-dependent inverted U-curve effect in both groups, in which lower doses increased and higher doses reduced compulsive drinking in SIP. Ketamine, cannabidiol, WIN21255-2, and AM404 did not have any relevant effects in SIP.

CONCLUSIONS

These data provide new evidence that low doses of scopolamine and intermediate doses of methamphetamine might therapeutically reduce compulsive behaviors and suggest that there is not a direct participation of the endocannabinoid system in compulsive behavior on SIP. The research in the underlying neurochemical mechanisms of these psychoactive drugs might provide an additional insight on new therapeutic targets in compulsive neuropsychiatric disorders.