The Department of Health and Social Care (DHSC) issued a medicine supply notification for isosorbide mononitrate 10mg, 20mg and 40mg immediate-release (IR) tablets on 19 December 2024. 

Prescribers should not initiate new patients on isosorbide mononitrate IR tablets until the supply issues have been resolved.

Where patients have insufficient supplies to last until the re-supply date(s), prescribers should:

• consider generically prescribing isosorbide mononitrate modified-release (MR) tablets or MR capsules, at an equivalent dose, during this time, if clinically appropriate, (see attached MSN for supporting information)
• ensure that the patient is not intolerant to any of the excipients 
• ensure the patient is counselled on the change in product, dosage, and possible adverse events they may experience, particularly in the first few days, the most important being hypotension, tachycardia, and worsening headaches. The patient should be advised to contact their prescriber if they have concerns.

Advice should be sought from the specialist team if the above options are not considered appropriate.

Refer to the MSN below for full supporting information and the SPS Medicines Supply Tool (you will need to log into the Specialist Pharmacy Service website).