Long term high dose ibuprofen can do some serious damage , bro in law has Crohns because of it.
He’s got a cold, presumably only going to take for a few days, take with food or speak to GP or pharmacist about getting a PPI like omeprazole.
Indeed, don’t take aspirin and ibuprofen together.
If you don’t like the lemsip capsules, just take plain old paracetamol and a plain decongestant or try a different brand of mix like Sudafed (those aren’t very big Iirc)