| Allocation: randomised, with sequence generation and concealment of allocation clearly described.
Blindness: single.
Duration: 1 month at least.
Raters: independent. | People diagnosed with a psychotic illness and having polydipsia secondary to this (polydipsia is defined as >3 litres of water per day).
N=300. | 1. Antipsychotics
For example clozapine, olanzapine and risperidone.
2. Antidepressants
For example, mianserin.
3. Beta adrenergic receptor blockers
For example, propranolol.
4. Angiotensin converting enzyme (ACE) inhibitors
For example, captopril and enalapril.
5. Mood stabilisers
For example, lithium.
6. Angiotensin II receptor‐blocking agents
For example, irbesartan.
7. Anticonvulsants
Only phenytoin was considered as it suppresses central release of vasopressin. Other antiepileptic drugs were not considered.
8. Tetracycline bacteriostatic agents
Only demeclocycline was considered.
9. Opiate antagonists
For example, naloxone.
10. Alpha adrenergic receptor blockers
11. Placebo | Primary outcomes
Death**
Lack of improvement in polydipsia, to a clinically significant degree**
No alleviation of polydipsia**
Leaving the study early, for specific or general reasons**
Symptomatic visceral oedema**
Emergence or worsening of physical symptoms secondary to increased fluid intake
Change in mental state
General functioning
Acceptability of treatment
Adverse effects of interventions
Economic evaluations: cost‐effectiveness, cost‐benefit.
Time periods: immediate term (within 24 hours) short term (up to one week), medium term (eight days to one month), and long term (more than one month). | *primary outcome. |
