A 34-year-old man attends the emergency department after cutting his forearm during an argument with his partner. The wounds are superficial and have been closed with tissue adhesive. He is medically fit and not intoxicated. He says he did not want to die and wants to go home. He took an overdose of tablets two years ago, lost his job last month and drinks heavily at weekends. A triage nurse has recorded a 'low risk' score on a self-harm risk scale. His observations are normal.

What is the most appropriate next step?