SINGAPORE – Medical experts emphasize that medications containing decongestant pseudoephedrine can still be used; however, caution is paramount for individuals with specific health concerns such as uncontrolled hypertension and kidney failure, which heighten the risk of adverse effects.

While there is no necessity to cease usage outright, experts urge strict adherence to prescribed dosages and immediate medical consultation if symptoms like nausea or visual disturbances occur. This advice comes in light of reports concerning pharmaceutical giant GSK's decision to discontinue Zyrtec-D, a well-known antihistamine and decongestant containing pseudoephedrine, raising awareness and concern among readers of The Straits Times.

Pseudoephedrine is present in approximately 30 approved medications in Singapore, including Clarityn-D, Telfast-D, and Sudafed. Despite its effectiveness as a decongestant, the drug has been associated with serious, albeit rare, side effects such as posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS).

PRES is a neurological condition characterized by symptoms such as headache, seizures, visual disturbances, and cognitive dysfunction. It is usually reversible with prompt treatment. On the other hand, RCVS mimics stroke symptoms due to spasming blood vessels, and around 30% of those affected may experience long-term disabilities like muscle weakness.

Dr. John Cheng, chief medical officer of Healthway Medical Group, clarified that these severe reactions are "exceedingly rare," often linked to a combination of factors such as pre-existing health conditions, overdosing, or simultaneous use of drugs that impair the central nervous system or influence blood pressure. He underscores the necessity for vigilance, especially for patients already facing risk factors like hypertension, migraines, or a history of stroke.

In response to potential risks associated with pseudoephedrine, Singapore's Health Sciences Authority issued a safety alert in April 2024, announcing plans to update warnings about PRES and RCVS in the product information for pseudoephedrine-containing medications. Healthcare professionals are encouraged to counsel their patients on symptoms that warrant immediate medical attention, which include severe headaches, visual disturbances, confusion, and seizures.

Further guidance from Britain’s National Health System (NHS) specifies that individuals with cardiac issues should avoid pseudoephedrine. The drug narrows blood vessels not only in the nasal passages but throughout the body, potentially raising blood pressure and heart rate. The NHS recommends caution for those with conditions such as glaucoma, enlarged prostate, or liver and kidney problems, and it cautions that usage should not exceed seven days due to increasing risks of side effects with prolonged use.

As we navigate the complexities of health and medications, staying informed and consulting with healthcare providers can ensure safer use of common decongestants like pseudoephedrine. So, before you reach for that next dose, consider your health background and consult a professional to steer clear of potential dangers!