Background:

There are a significant number of patients admitted to our acute hospitals with physical health problems who are currently prescribed clozapine (Care Quality Commission, 2023). 

Some patients presenting to the Emergency Department (ED) or wards may have missed doses of their medication due to nursing or medical staff being unaware that patient was taking clozapine or the supply not coming with the patient.

Objectives:

This study aimed to discover why patients were admitted, whether they were concordant with their medication whilst an inpatient, if staff were aware of how critical it was to administer clozapine as prescribed and if any complications due to clozapine arose on admission. 

Further objectives were to ensure clozapine plasma concentrations were monitored throughout admission.

Design:

A retrospective analysis was conducted of patients prescribed clozapine who were admitted to a general medical hospital in a 24-month period. 

Ten (18%) of those admitted were admitted on average of 5 times (Graph 1) within this time period with the same or similar issue.

Method:

Data was collected using electronic drug charts which is primarily used within the Intensive Care Units. Paper kardex’s which are used within both the Emergency Departments and also the hospital wards as well as correspondence with the drug manufacturer Zaponex (Zaponex, 2024) and finally the patients clinical notes.

Results:

In total, 66 (100%) individual clozapine patients were hospitalised. 4 patients (6%) were admitted because of infection, 3 (5%) presented with a psychotic presentation, 3 (5%) were admitted due to a recreational drug overdose, 2 (4%) were due to Neuroleptic Malignant Syndrome (BMJ Best Practice, 2024), 4 (6%) admitted with an infection, 9 (15%) were waiting in ED for a Mental Health bed, 14 (18%) were admitted due to other medical reasons and were referred for monitoring of clozapine and 8 (12%) had gastrointestinal problems mainly bowel obstructions (Gov.uk, 2017) (Graph 2), all but 1 patient had been prescribed laxatives.

Few changes were made to clozapine dosing on admission or during the inpatient stay however 3 (5%) patients did have to have their clozapine omitted and subsequently had to retitrate back to their original therapeutic dose, this was initiated in the acute hospital but the titration in all cases were completed in a mental health hospital setting, 2 individuals had to have their clozapine stopped indefinitely due to physical health complications. Clozapine plasma concentrations were monitored throughout admission on 23 (35%) (Graph 3)  of our patients, of those not monitored it was due either to the fact they were waiting in ED for an acute mental health admission or that their admission to the general setting was a short admission with no concerns identified regarding the patients medication. 

Two patients were admitted to our Intensive Care Unit (ICU) department unit during their admission due to a deterioration in their physical health and this was in one case Neuroleptic Malignant Syndrome and in another it was due to Bowel obstruction, only 1 (2%) patient was discharged on clozapine. 

Within the ED department 3 (5%) of patients had missed at least 1 dose of clozapine and 1 (2%) patient had not received their prescribed dose for over 24 hours. This patient presented on a Friday evening with no supply of medication with them and staff were unaware of how critical it was for the patient to receive their clozapine and were also unaware that the patient was prescribed clozapine.

Conclusions:

This study found the most common reasons for admission for those patients currently prescribed clozapine were gastrointestinal issues with other medical reasons and toxicity accounted for 22% of admissions. 

Factors which we had to take into account were that the team also perform Crisis Assessments and if a patient is deemed that they require an acute mental health hospital admission they have to remain in our ED until a bed can be sourced.

In respect to the missed doses of clozapine we have been proactive in educating staff, we completed a survey of 55 nursing and medical staff (Graph 5) within the general hospital setting and found that 43 out of 55 had limited awareness of clozapine prior to educational sessions compared to 12 who had an awareness, as this study was over the past 24 months we have had only 2 cases (Graph 4) within the past 12 months showing that proper education is vital in supporting our colleagues within a general medical setting consequently an educational programme was developed to raise awareness of clozapine.

References:

BMJ Best Practice (2024) Neuroleptic malignant syndrome. Available at: https://bestpractice.bmj.com/topics/en-gb/3000227 (Accessed: 04th November, 2024)

Care Quality Commission (2023) High risk medicines: clozapine. Available at: https://www.cqc.org.uk/guidance-providers/adult-social-care/high-risk-medicines-clozapine (Accessed: 22nd October, 2024)

Gov.uk (2017) Clozapine: reminder of potentially fatal risk of intestinal obstruction, faecal impaction, and paralytic ileus. Available at: https://www.gov.uk/drug-safety-update/clozapine-reminder-of-potentially-fatal-risk-of-intestinal-obstruction-faecal-impaction-and-paralytic-ileus Accessed: 07th November, 2024)

Zaponex (2024) Zaponex (clozapine) Tablets. Available at: https://www.zaponex.co.uk/zaponex-clozapine-tablets. (Accessed: 13th November, 2024)