Lack of competence in caring for patients and neglect are the biggest drivers of complaints to the Nursing and Midwifery Council, a breakdown of referrals to the regulator has revealed.
It is the first time the NMC has published a detailed analysis of the reasons behind the thousands of referrals it receives about nurses and midwives in the UK every year.
Just under half related to misconduct, 29% to lack of competence and 16% to potential criminal behaviour.
There were 618 allegations of patient neglect, 152 that a nurse had been violent towards or physically abused a patient and 124 that a nurse had been verbally abusive to someone in their care.
A total of 105 referrals alleged that registrants had stolen drugs, 55 that a nurse had been sleeping on duty while 44 related to inappropriate use of social media.
There were 4,407 referrals in 2011-12, almost double the number received in 2009-10 and a 4.7% rise on 2010-11.
However the proportion of allegations found to have no case to answer has increased from 38% in 2009-10 to 55% in 2011-12, suggesting an increase in inappropriate referrals.