Red flags

Psychiatric disorders (i.e. polydipsia) can be associated with polyuria, but the patient has no medical history of mental health issues and is showing no such symptoms on presentation.

Management

• Self-care options

Given his symptoms, there are no self-care options that should be recommended.

• Prescribing options

Tests can be performed to check for diabetes mellitus and diabetes insipidus. Your thinking is leaning towards diabetes mellitus, so these tests need to be conducted first. As the patient is symptomatic, a single abnormal HbA1c (>48mmol/mol) or fasting plasma glucose level (>7.0mmol/L) can be used.

Safety netting

You inform the patient that because he has had symptoms for some time, you feel it best that he has some blood tests as you cannot rule out that his symptoms are being caused by diabetes. These tests need to be arranged with his GP practice.