That persistent sore throat and feeling of weariness will not go away. Painkillers seem the only option for masking the symptoms of your bad cold. Usually it would be a simple choice of opening the medicine cabinet and selecting the painkiller of your choice, but tonight’s plan is to meet your friend at the pub for a few drinks. Which painkiller should you choose?
The NHS does not make specific recommendations. They advise that over-the-counter painkillers should be safe at the recommended dose if the daily alcohol limit is not exceeded. This equates to 1-2 glasses of wine or 1-2 pints of beer. Sounds very sensible, but this is your friend’s birthday. One glass of wine seems unlikely!
The risks will differ depending on the type of painkiller and its mechanism of action. There are two main types of painkillers, those that prevent chemical messengers from alerting neurons to sense pain and prevent inflammation, and those that prevent the action of a subset of the chemical messengers linked to pain sensation. The painkillers that indiscriminately act on chemical messengers include aspirin and ibuprofen. The painkiller that prevents some of the chemical messengers is paracetamol, also known as acetaminophen in the US.1
Aspirin and ibuprofen
In addition to stymieing pain, aspirin and ibuprofen also target the chemical messengers protecting the stomach lining, increasing the risk of bleeding. Drinking alcohol without painkillers may damage the stomach too.2 An observational study suggests that together, the painkillers and alcohol increase the risk of bleeding even more in those who consume both regularly.3 However, for the regular drinker but the occasional user of aspirin or ibuprofen, the risk of stomach bleeding is not increased. The limited evidence available suggests that even if one were to drink regularly, the occasional aspirin or ibuprofen would not cause additional harm to your stomach.
In contrast to aspirin and ibuprofen, paracetamol selectively targets chemical messengers involved in sensing pain, so it does not harm the stomach. When paracetamol is broken down in the body, some of it becomes toxic to the liver. Taking paracetamol without alcohol is associated with an increased risk of liver damage, and more-so at doses higher than recommended.4 From 1993-1997, hundreds of patients died from paracetamol-related liver damage in England and Wales.
Paracetamol plus alcohol is thought to increase the risk of liver damage more than paracetamol alone, as mice given both have more paracetamol toxins.5 As it would be unethical to give patients paracetamol and alcohol, few studies have been done in humans. However, in an observational study of patients hospitalised for paracetamol-induced liver issues, recent alcohol use combined with excessive paracetamol use was significantly associated with liver damage, but not when alcohol was combined with the recommended dose of paracetamol.6 The results suggest excess paracetamol plus alcohol could cause liver issues, but recommended doses of paracetamol plus alcohol would not cause harm.
The limited available evidence from observational studies suggests that the risk of side effects from combining alcohol with over-the-counter painkillers would be low for the social drinker who infrequently uses painkillers at recommended doses. As more studies are needed to confirm this, the safest option would be to follow the NHS’s advice to keep to the recommended daily limits for both painkillers and alcohol.
2 Tarnawski A, Hollander D, Stachura J, Klimczyk B, Mach T, & Bogdal J (1987). Alcohol injury to the normal human gastric mucosa: endoscopic, histologic and functional assessment. Clinical and investigative medicine. Medecine clinique et experimentale, 10 (3), 259-63 PMID: 3621711
3 Kaufman DW, Kelly JP, Wiholm BE, Laszlo A, Sheehan JE, Koff RS, & Shapiro S (1999). The risk of acute major upper gastrointestinal bleeding among users of aspirin and ibuprofen at various levels of alcohol consumption. The American journal of gastroenterology, 94 (11), 3189-96 PMID: 10566713