A prison doctor rated a murder suspect found dead in his cell not to be at risk despite him seriously injuring himself just two days before the assessment, a court heard.

Father-of-two Adrian Johnson, 27, tied a TV aerial around his neck in an apparent cry for help at HMP High Down on May 8, 2010, stating his main cause of distress as a withdrawal of cigarettes, Southwark Coroner’s Court heard on Tuesday.

Just days later, on Thursday, May 13, 2010, he was found dead in his cell after he was transferred to Belmarsh Prison, in Thamesmead.

Mr Johnson was transferred to Belmarsh following his appearance at the Old Bailey on Monday, May 10, and was assessed by nurses as low risk before being seen by Doctor Hanna Kucper.

Giving evidence on Thursday Dr Kucper, who could not remember Mr Johnson, rated him as not being at an immediate risk of self harm or suicide.

When questioned by Southwark Coroner Dr Andrew Harris about why she had given the rating Dr Kucper said: "I would think that the way he answered my questions and presented to me didn’t indicate to me he had any intention of self harm or suicide at that time."

The court heard Dr Kucper was unaware Mr Johnson had suffered two recent episodes of confusion including a phone call when he wrongly thought it was his son’s birthday and being unaware of the offence with which he had been charged.

When asked about his smoking Dr Kucper said she had never had a patient come in that was agitated by a lack of tobacco.

Coroner Dr Harris said: "[Tobacco withdrawal] is a clinical concern, has a range of symptoms and there are treatments available. Were you aware Mr Johnson gave the reason for putting the ligature around his neck as the fact he could not get enough tobacco?"

Dr Kucper: "It was mentioned in the ACT document [a care risk assessment] but I don’t think I had the knowledge of it at the time."

She said that even if she had known he had tied a ligature around his neck due to tobacco withdrawal she would not have done anything different.

She added that patients who are dependent on nicotine did not come under the care of the substance misuse team of the GPs in the prison. Dr Kucper did not ask how much Mr Johnson smoked.

Coroner Dr Harris said: "I put it to you that you failed to take adequate history to identify the potential life-threatening action and the clinical steps needed to address them."

She replied: "I don’t think it was my duty. My duty was to refer him urgently to the mental health team. They would assess the patient and find out the under-lying symptoms of self harm and suicide attempt."

The court heard Mr Johnson, who smoked 40 cigarettes a day, was given 12.5grams of tobacco on his first night in Belmarsh.

Mr Johnson, a former warehouseman, was charged with stabbing to death 49-year-old Robert Anthony Lewis and with assaulting Colin Buckfield at a shared home for vulnerable adults in Cheam Road, Sutton, on May 4.

The jury inquest, that is set to hear from 36 witnesses and is listed for three weeks, continues.