DRAP’s Safety Alert Regarding Mesalazine!
Risk of Idiopathic Intracranial Hypertension Associated with Mesalazine
Date: 30 January 2026
Target Audience
Provincial Health Departments / Provincial Pharmacovigilance (PV) Centres
Manufacturers and importers of mesalazine
Healthcare professionals
Patients
Background
The Health Products Regulatory Authority (HPRA) of Ireland announced in its Drug Safety Newsletter (June 2025) that the product information for mesalazine has been updated to include a risk of idiopathic intracranial hypertension (IIH), also referred to as pseudotumor cerebri.
The European Medicines Agency’s Pharmacovigilance Risk Assessment Committee (PRAC) reviewed available evidence from published literature and spontaneous adverse event reports. In several cases, a close temporal relationship, positive de-challenge, and/or re-challenge was observed. Based on this evidence, PRAC recommended that warnings regarding IIH be added to the product information for all mesalazine-containing products. If IIH occurs, discontinuation of mesalazine should be considered. Importantly, the overall benefit–risk balance remains unchanged for approved indications.
Similarly, the UK Medicines and Healthcare products Regulatory Agency (MHRA) issued a Drug Safety Update on 4 December 2025, reporting that idiopathic intracranial hypertension has been very rarely reported in patients treated with mesalazine. Following a European safety review, the MHRA confirmed that warnings for IIH are being incorporated into the product information of all mesalazine products.
The findings were reviewed by the Pharmacovigilance Expert Advisory Committee (PEAG) of the UK Commission on Human Medicines (CHM), which endorsed the recommendations and advised informing healthcare professionals and patients of this potential risk. The number of reported cases remains very low; in the UK, six Yellow Card reports of increased intracranial pressure disorders associated with mesalazine have been received.
DRAP’s Regulatory Action in Pakistan
This safety signal was discussed during the 6th meeting of the Pharmacovigilance Risk Assessment Expert Committee (PRAEC) held on 31 December 2025. In accordance with Rule 10(1)(h)(iv) of the Pharmacovigilance Rules, 2022, PRAEC decided that:
Marketing Authorization Holders must update the Warnings and Precautions section of the Summary of Product Characteristics (SmPC) and labeling to include the risk of idiopathic intracranial hypertension.
IIH should be listed in the Adverse Drug Reactions (ADRs) section with a frequency of “not known.”
These updates are to be implemented for all mesalazine-containing products marketed in Pakistan, in alignment with the MHRA-UK decision.
Therapeutic Goods Affected
Mesalazine (5-aminosalicylic acid): An intestinal anti-inflammatory agent indicated for:
Treatment of mild to moderate ulcerative colitis (acute phase and prevention of relapse)
Treatment of Crohn’s disease (acute phase and prevention of relapse), where disease is limited to the colon
Advice for Healthcare Professionals
Healthcare professionals should be aware that idiopathic intracranial hypertension has been very rarely reported in patients receiving mesalazine. Patients should be advised to monitor for symptoms suggestive of IIH, including:
Severe, persistent, or recurrent headache
Visual disturbances
Ringing or buzzing in the ears (tinnitus)
Clinicians should remain vigilant for signs and symptoms of IIH and manage suspected cases promptly using a multidisciplinary approach, involving gastroenterology, neurology, neurosurgery, and ophthalmology teams as appropriate. If IIH is suspected or confirmed, discontinuation of mesalazine should be considered, and appropriate management initiated immediately.
Caution is advised when prescribing mesalazine to patients with a history of diagnosed or suspected IIH.
Advice for Patients
Patients are informed that there have been very rare reports of increased pressure within the skull, known as idiopathic intracranial hypertension, in individuals taking mesalazine. While IIH is generally not life-threatening, it can, in rare cases, lead to serious vision problems if not identified and treated promptly.
Patients should contact their doctor immediately if they experience:
Worsening or recurrent headaches
Blurred or disturbed vision
Ringing or buzzing in the ears
Dizziness, neck pain, or back pain
Reporting of Adverse Drug Reactions
Healthcare professionals and patients are encouraged to report any suspected adverse drug reactions or events associated with mesalazine or other medicines through the National Pharmacovigilance Centre (NPC) via the Med Vigilance E-Reporting System (E-Forms) available on the DRAP website. Adverse events may also be reported using the VigiMobile App.
How to download VigiMobile App
Reference
Drug Regulatory Authority of Pakistan. (2026, January 30). Safety alert of risk of idiopathic intracranial hypertension with mesalazine. https://www.dra.gov.pk/safety_info/safety_communication/safety_updates/safety-alert-of-risk-of-idiopathic-intracranial-hypertension-with-mesalazine/
