6 surprising foods and drinks that could affect your medication

When you're prescribed a new medication, it might be tempting to add taking it to your daily routine without making any other adjustments to your diet. But depending on what you're taking, this could be a major mistake. 

Here, we take a look at some of the things that can impact common prescription medications, from the relatively well known to the unexpected. 

It's not an exhaustive list, so you should always read the advice that comes with any new meds, and ask your GP or pharmacist if you're unsure. 

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1. Grapefruit juice

This bitter breakfast drink is known to interact with a number of common medications, in potentially dangerous ways.

It blocks the enzymes that break down some medicines, which means you can get a much higher dose than expected. This is particularly dangerous if you're taking drugs could have serious side effects, as it'll make them more likely. In some cases, it can also cause too little of other drugs to enter your system, reducing their effectiveness. 

Common meds it's known to interact with: statins, calcium channel blockers, antidepressants, immunosuppressants, anticoagulants, cytotoxic medicines - and more

2. Liquorice

Much like grapefruit juice, liquorice isn't to everyone's taste. But if you're partial, you should double-check your medication leaflet to make sure it won't do more harm than good, as excessive amounts can impact blood pressure and potassium levels, among other things.

If you're on medication that might be affected, be aware it can crop up in unexpected places, including many herbal tea blends - so it's worth checking the ingredients first (as it's not always listed on the front). 

Common meds it's known to interact with: blood pressure medicine, diuretics, hormone therapy drugs, blood thinners and more

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3. Herbal supplements

Herbal supplements are generally classed as food supplements, unless they make specific health claims, so don't need to come with extensive information leaflets. But, while they may be food or nature-based, that doesn't mean they're benign.

Some can impact the way your medication works, especially if in higher doses than you'd typically eat.

Supplements such as St John's wort and gingko biloba are known to interact with some medications, and typically carry a warning, but it's always best to tell your GP or prescriber if you're taking any supplements, to ensure the combination is safe.

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4. Alcohol

Alcohol is one of the more obvious interactants on this list. Drinking to excess is bad for your health regardless of whether you're on medication, but people on certain medications should take special care. 

With some medications, you're advised to avoid alcohol altogether, while with others you should just limit your consumption. If you're taking statins, for example, you shouldn't drink more than 14 units of alcohol a week. 

Avoid if you're taking: antidepressants, certain sedatives, some antihistamines and more

5. Strong cheeses

This one's very specific. If you're taking MAOIs - a less commonly prescribed type of antidepressant - there's a chance your favourite stinky cheese could have serious side effects. 

MAOIs stop your body from breaking down a chemical called tyramine, which these cheeses include. So eating them could lead to a dangerous increase in your tyramine levels. 

Avoid if you're taking: MAOI antidepressants

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6. Herbal teas

Depending on the blend, sipping too much of certain types of herbal tea could also impact the effectiveness of your medication. 

We've already mentioned that liquorice, found in some herbal teas, could affect your medication. The same is true of other herbs you might want to drink warmed up. Popular herbal teas like green tea and ginseng have been found to affect some drugs in clinical studies. 

Avoid green tea if you're taking: certain cardiovascular drugs

The bottom line is, it's really worth reading up on new medication, and checking anything you're unsure of with a pharmacist, so you can ensure you're not unwittingly messing up how it works, and avoid anything potentially aggravating.

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