Some things don’t mix well. We already know that some medicines when taken together do not work well, what we refer to as dangerous drug interactions. Some food and drink we take can also have an effect on our medications too. Hence, before you take a medication for the first time, talk with your doctor or pharmacist to see if there are foods or beverages he may advise you to stay away from.

Some examples of popular foods and beverages that can interact with our medications include:

  1. Grapefruit

This fruit can change the way certain cells in your gut take in and move medication through your body. This can affect more than 50 drugs. It can make some drugs less effective – e.g. fexofenadine (Allegra) for allergies, and make others too strong – e.g. atorvastatin (Lipitor) that is used to lower blood cholesterol.

  1. Milk

This dairy product can make it harder for your body to process certain antibiotics. Minerals in milk like calcium and magnesium are responsible for this effect, along with the protein casein. If you’re taking antibiotics, make sure to find out if taking a lot of milk can reduce the effectiveness of your medication.

  1. Chocolate

Dark chocolate is a form of chocolate which contains a higher percentage of cocoa solids and cocoa butter than milk chocolate, and little to no dairy product. Dark chocolate in particular can weaken the effects of drugs meant to calm you down or make you sleep, like zolpidem tartrate (Ambien). It also can boost the power of some stimulant drugs, like methylphenidate (Ritalin). And if you take an MAO inhibitor, used to treat depression, it can make your blood pressure dangerously high.

  1. Alcohol

Alcohol often has harmful interactions with prescription medications, over-the-counter drugs, and even some herbal remedies. Alcohol interaction with medications may cause nausea and vomiting, headaches, drowsiness, dizziness, fainting, changes in blood pressure, abnormal behavior, loss of coordination and accidents. Mixing alcohol and medications also may increase the risk of complications such as – liver damage, heart problems, internal bleeding, impaired breathing and depression. In some cases, alcohol interactions may decrease the effectiveness of medications or render them useless. In other cases, alcohol interactions may make drugs harmful or even toxic to the body.

  1. Coffee

It can weaken antipsychotic drugs like lithium and clozapine, but boost the effects and side effects of others. Drugs affected include but not limited to aspirin, epinephrine (used to treat serious allergic reactions), and albuterol (taken by inhaler for breathing problems). It can also make it harder for your body to take in and use iron.

  1. Spinach

Spinach is a rich source of Vitamin K. If you are taking the drug warfarin – a blood thinner, used to treat and prevent blood clots — be aware of how much vitamin K you take in. It can make Warfarin less effective and put you at higher risk of a dangerous blood clot. Spinach, Broccoli, Brussels sprouts, kale, and parsley are some of the most common foods high in vitamin K. Try to eat the same amount of these foods every day so the level of warfarin in your blood stays the same.

  1. Ginseng

Ginseng is a popular component of many herbal teas. Ginseng can lower the effects of warfarin, too. It also increases your risk of internal bleeding if you take the blood thinners heparin or aspirin, as well as non-steroidal anti-inflammatory drugs like ibuprofen or naproxen. If you take MAO inhibitors, ginseng can cause headaches, sleep problems, hyperactivity, and nervousness.

  1. John’s Wort

This is an herbal remedy sometimes used to help people with depression. It is not a proven treatment for depression or any other health condition. It can make your liver release enzymes that can weaken the effect of some medications. Drugs that can be affected include cholesterol drugs like lovastatin (Altoprev and Mevacor), the erectile dysfunction drug sildenafil (Viagra), and digoxin (Lanoxin), used to treat certain heart conditions.

In conclusion, now that you are aware of the different foods and beverages that may affect the medication you take, make sure you check carefully before you take any medication and always confer with your prescriber when you have doubts. Remember that this list is not exhaustive and there are other numerous food-drug interactions which may be harmful to your body. This is why it is most important that you only take drugs as prescribed by your doctors.

Credits: WebMD, Mayo Clinic, CDC, WHO

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