We asked Professor Paul Wallace why doctors sometimes tell us not to drink when we take prescription drugs, and what happens if we do.
Professor Wallace says the question as to whether you should drink alcohol while on medication depends entirely on what medication you’ve been prescribed.
For some types of medication it’s OK to drink within the government’s low risk alcohol unit guidelines (no more than 14 units a week for both men and women). However, for some, alcohol should be completely avoided.
Professor Wallace says that:
- People taking sedative drugs (like diazepam/Valium) or antidepressants (like fluoxetine/Prozac) should avoid alcohol altogether
- There are some antibiotics which simply do not mix with alcohol - drinking with these will make you sick. But for most commonly prescribed antibiotics, drinking is unlikely to cause problems so long as it is within the low risk alcohol unit guidelines.
- People taking long-term medications should be careful about drinking, as alcohol can make some drugs less effective and long-term conditions could get worse. Examples of long-term medications include drugs for epilepsy, diabetes, or drugs like warfarin to thin the blood.
- There’s no evidence to prove that alcohol can improve your immune system. The positive effects of a hot drink with alcohol in it (sometimes called a ‘hot toddy’) are probably psychological.
Professor Wallace says there are two main reasons why doctors advise patients not to drink with some drugs.
- “Firstly, because alcohol is a depressant, it affects the way your brain works, numbing your senses so they don’t operate properly,” he says. “Some types of medication also affect the way your brain works, and if you’re drinking alcohol there will be a conflict. Alcohol will increase the sedative effects of both, causing sleepiness and dizziness. It could also change the way the brain responds to the medication, making it less effective.” If you’re taking a sedative drug, such as diazepam/Valium, or any other drug that can make you drowsy, and you drink alcohol, your reaction times could decrease and you’ll get tired faster. If you’re driving or operating machinery, this can be extremely dangerous.
- “Secondly, alcohol can affect the way drugs are absorbed by the body and broken down in the liver,” says Professor Wallace. "If you drink alcohol regularly and especially if you drink excessive amounts, your liver produces more enzymes so that it can get rid of the alcohol more quickly. Those same enzymes might break down the medication you are taking so it no longer has the same effect. An example of this is medications for epilepsy."
When it comes to antibiotics, Professor Wallace says that the message is slightly different than it is with sedative drugs. The NHS advises that people who choose to drink alcohol when taking most common antibiotics do so within the weekly alcohol unit guidelines1
There are antibiotics, like Metronidazole and Tinidazole, which you should not drink alcohol with. Mixing them with alcohol can lead to nausea, vomiting, flushing of the skin, accelerated heart rate or shortness of breath. This is because they can interfere with the breakdown of alcohol, leading to the production of nasty side effects2.
There are a wide variety of antibiotics available, penicillin and amoxicillin are the most widely used.
These can have different interactions with alcohol, and, as with any medication, you should always consult your doctor or pharmacist about guidelines regarding consumption.
Statins are drugs which are taken to lower the levels of cholesterol in your blood. High levels of ‘bad cholesterol’ can increase the risk of developing cardiovascular disease due to fatty deposits building up in your arteries.
According to the NHS, there are no known interactions between statins and alcohol3. However, consumption of statins can occasionally result in an increase in liver enzymes, which if left un-checked can lead to liver damage. It is therefore important for those taking statins to stay within the government’s low risk alcohol unit guidelines (of no more than 14 units per week for both men and women) and to have their liver function tested periodically.
As with any medication, you should always consult your doctor about consumption guidelines.
Can alcohol itself ever be a good medicine? Professor Wallace explains how alcohol was once used in medical practice and gives his medical conclusion on alcoholic hot drinks being used as remedies.
“Before the advent of modern anaesthetics, when surgeons were performing operations, they would use alcohol as an anaesthetic, getting their patients drunk before they operated,” he explains. Professor Wallace says the reason for this is because alcohol numbs the brain.
He also explains that many people also feel better after having a ‘hot toddy’ (hot drink with whisky) when they have a cold because alcohol also numbs your senses. A hot toddy can make you feel better but there’s no evidence to suggest that it actually improves your health.
“Nobody should kid themselves that it is going to help you actually get better,” says Professor Wallace.
“You may experience an immediate gain because alcohol has numbed your senses and made you feel less bad for a short time. But you’re deceiving your body and slowing your recovery.”
There’s no firm evidence about the effects of alcohol on the immune system, but Professor Wallace thinks it’s probably not a good idea to drink alcohol when you are feeling ill because it is likely to make you feel worse. “Our state of mind can affect the way we respond to illnesses and alcohol is, after all, a depressant,” says Professor Wallace.
If you’re taking prescription drugs and are unsure whether it is safe to drink alcohol, the best advice is to check with your doctor and the pharmacist. Also check the leaflet that comes with the medication.
Professor Wallace advises that: “If you’re in any doubt, don’t drink alcohol at all because you could put your health at risk.”
(1) and (2) NHS Choices website. Can I drink alcohol while taking antibiotics? The Information Standard member organisation. Last reviewed: 8/05/2015. Available at: http://www.nhs.uk/chq/Pages/871.aspx?CategoryID=73&SubCategoryID=103
(3) NHS Choices website. Cholesterol-lowering medicines, statins - Interactions. The Information Standard member organisation. Last reviewed: 25/03/14. Available at: http://www.nhs.uk/Conditions/Cholesterol-lowering-medicines-statins/Pages/Special-considerations.aspx