Analgesics
In January 2018, co-dydramol (dihydrocodeine/paracetamol) became available in higher strengths of dihydrocodeine (co-dydramol 20/500mg and 30/500mg tablets). Co-dydramol products must be prescribed and dispensed by strength and dose to minimise errors and the risk of accidental opioid overdose. Where the strength is not stated the prescriber should be contacted.
More cases of life-threatening and fatal opioid toxicity reported to the MHRA have been from accidental exposure to transdermal fentanyl patches, particularly in children. Patients should be warned not to exceed the prescribed dose and follow the correct frequency of patch application, paying particular attention to avoid touching the adhesive side of patches, and washing hands after application. Patches must not be cut or exposed to heat (this includes hot baths and showers).
Old patches must be removed before applying new ones and the old patch must be folded over so the adhesive side adheres to itself, placed in the original sachet and stored safely out of the reach of children. Used patches can cause fatalities. Signs of fentanyl overdose require immediate attention and patches must be removed immediately if severe adverse events occur.
Additional TSH monitoring required
The MHRA received reports of interactions with regards to ritonavir-containing products with levothyroxine leading to reduced thyroxine levels. It is now recommended that thyroid-stimulating hormone (TSH) is monitored in patients treated with levothyroxine for at least the first month after starting and ending ritonavir treatment. As with all suspected drug interactions, these must be reported using the Yellow Card system.