Hospital Pharmacist
2008;15:4
January 2008

News summary

SSRIs might interact with methyl blue

Hospital pharmacists working in pre-admission clinics should remain vigilant for a potential interaction between methylthioninium chloride (methylene blue) and serotonergic drugs, according to the Medicines and Healthcare products Regulatory Agency.

Central nervous system toxicity has been reported to the MHRA after using methylene blue as a contrast medium for parathyroid or thyroid surgery on 27 occasions. In all but one occasion, the patient was also receiving a serotonergic drug.

In most cases, CNS toxicity occurred within a few hours of surgery and manifested as confusion and disorientation.

The recommendations are published in the January 2008 edition of Drug Safety Update