A couple of days ago I realised that my Tresiba had expired 2 months ago. Checking back, it was prescribed at the end of December, so only had a 4 month shelf life. I only take 6 units a day, so had only just started using the 2nd pen, so I’ve had to dispose of 2 full pens. What’s waste. I asked my nurse to reduce my prescription to 2 pens, and the new ones have an expiry date of june 26. I think the insulin was still ok as I’ve had no problems with my blood sugar recently. But note to myself, check the dates before you accept them !