Summary Safety Review - Atypical antipsychotics - Assessing the Potential Risk of Urinary Retention

October 21, 2016

Product

Atypical antipsychotics

Potential Safety Issue

Difficulty urinating or inability to completely empty the bladder (urinary retention)

Key Messages

• Atypical antipsychotics are used to treat mental disorders including schizophrenia, bipolar disorder and, in some cases, depression.
• The safety review of atypical antipsychotics and urinary retention was triggered by new safety information received from the manufacturer of Seroquel (quetiapine).
• Health Canada’s safety review found a potential link between the use of atypical antipsychotics and urinary retention. Health Canada is working with the manufacturer of olanzapine to update the safety information to increase the strength of the warning of the potential risk of urinary retention. Currently labelling for this risk is adequate in other antipsychotics in the Canadian market.

Overview

Health Canada carried out a safety review to look into the use of atypical antipsychotics and the potential risk of having difficulty urinating or not being able to fully empty the bladder (urinary retention). This can be an emergency that requires medical attention. This review was triggered by new safety information received from the manufacturer of Seroquel (quetiapine) that included reports of urinary retention in patients using quetiapine. Health Canada reviewed evidence that may have also linked this side effect to other atypical antipsychotics available in Canada.

Use in Canada

• Atypical antipsychotics are used to treat psychiatric disorders such as schizophrenia, bipolar disorder, and in some cases, depression. Risperidone is also used for the short-term symptomatic management of aggressive behaviour and psychotic symptoms in severe Alzheimer-type dementia.
• Nine different atypical antipsychotic medications have been marketed in Canada since 1991, available by prescription only: Abilify (aripiprazole), Saphris (asenapine), Clozaril (clozapine), Latuda (lurasidone), Zyprexa (olanzapine), Invega (paliperidone), Seroquel (quetiapine), Risperdal (risperidone) and Zeldox (ziprasidone). Some of these medications are available as generic versions.

Safety Review Findings

• At the time of the review, Health Canada had received 38 Canadian reports ^{Footnote 1} related to urinary retention and the use of atypical antipsychotics (none with lurasidone use).
• The reports above, as well as those from published literature, noted that most patients recovered or were recovering from the side effects after stopping the antipsychotic medication. In some cases, urinary retention re-occurred after the drug was taken again, further supporting a potential link between the atypical antipsychotic and urinary retention.
• At the time of the review, there were 1254 international reports of urinary retention with the use of any of the atypical antipsychotics.
• The risk of urinary retention is mentioned in the product safety information for most of the atypical antipsychotics. However, the wording used to explain the risk of urinary retention for the approved drug olanzapine was not consistent with the evidence reviewed.

Conclusions and Actions

• Health Canada’s safety review found evidence supporting a potential link between the use of atypical antipsychotics and the occurrence of urinary retention.
• Health Canada will be updating the information for olanzapine to highlight what is currently known about the risk of urinary retention when this drug is taken. The update will be consistent with the safety information provided for the other products, which is considered at this time to be sufficient to remind about the risk of urinary retention.
• Health Canada will continue to monitor safety information involving atypical antipsychotics, as it does for all health products on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely action if and when any new health risks are identified.

Additional Information

The analysis that contributed to this safety review included scientific and medical literature, Canadian and international adverse reaction reports and what is known about the use of this drug both in Canada and internationally.

For additional information, contact the Marketed Health Products Directorate.