Cold and flu drugs fall into three broad camps: household names such as Lemsip and Sudafed; supermarket own-label alternatives; and single-ingredient medicines containing paracetamol or ibuprofen.
The difference in price can be striking.
A packet of 16 Lemsip All-In-One Max Strength tablets retails at £7.30, more than 20 times the £0.35 cost of paracetamol pills in some supermarkets.
Both contain 500mg of paracetamol, which doesn’t treat the underlying infection but does relieve pain and can bring down a fever.
The Lemsip version, along with many of its competitors, also contains the decongestant phenylephrine.
It’s meant to constrict leaky or swollen blood vessels in the nose which can cause congestion.
But Prof Lawrence says there is little evidence it works when taken as a tablet, rather than as a nasal spray, because much of the drug is broken down before it can reach the bloodstream.
In 2024, the US drug regulator said it wanted phenylephrine removed from all cold and flu pills, saying it was simply not effective, although that proposal has yet to be finalised.
Some cold and flu remedies contain a third active ingredient – guaifenesin – which is meant to loosen mucus in the airways.
That sits in more of a grey area: some studies report improvements in chest congestion, while others find little or no benefit.
A spokeswoman for Reckitt, which owns Lemsip and Nurofen, said the ingredients in its products are approved by regulators and formulated for multiple symptoms including fever, congestion and coughs.
