MHRA Alert- Pseudoephedrine: very rare risk of posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS)

• Healthcare professionals should note PRES and RCVS symptoms: sudden severe headaches, nausea, vomiting, confusion, seizures, and visual disturbances.
  

• PRES and RCVS are very rare side effects of pseudoephedrine, used for nasal and sinus congestion relief in colds, flu, and allergies. Pseudoephedrine should be used only short-term and not for prolonged periods.
  

• Avoid pseudoephedrine in patients with severe or uncontrolled hypertension or severe renal disease.
  

• Report any suspected adverse reactions to pseudoephedrine using the Yellow Card system.
  

• Advise patients that pseudoephedrine is for short-term relief of nasal and sinus congestion.
  

• Inform patients about the rare risks of PRES and RCVS and instruct them to stop the medication and seek urgent medical help if they experience severe headaches, nausea, confusion, seizures, or visual changes.
  

• Encourage patients to read the Patient Information Leaflet and consult healthcare professionals if they experience any side effects.
  

https://www.gov.uk/drug-safety-update/pseudoephedrine-very-rare-risk-of-posterior-reversible-encephalopathy-syndrome-pres-and-reversible-cerebral-vasoconstriction-syndrome-rcvs