When certain foods interfere with drugs

Monday February 17 2020


By Josephat Wangwe

Whenever you pick up a prescription medication, you may be given instructions by your doctor or notice little stickers on the bottle that say, “Take on an empty stomach” or “Take with food.” You may also find similar instructions on the nonprescription (over-the-counter) Drug Facts label as well.

Most people understand that some medications can interact with other medications, but did you know that food can affect how your medication works as well? It’s important to understand this issue so you can get the most out of your treatment.

Drug-food interaction is yet another factor, which might interfere the mechanism on how the medicine should perform.

The foods we eat can interfere with the medications we take.

Patients may not recognise that otherwise healthy foods can have severe consequences when mixed with certain drugs.

Food is a vital component in our well-being and has a great impact on the drug’s performance. It is a sacred role for a pharmacists, nurses, doctors and other medical practitioners to advise patients either to take medications after, with, before food or on an empty stomach.


But same role is entrusted to patients as well where by a patient has to ask various questions concerning the proper use of medicines when visiting local pharmacies, after being discharged from the hospital or being given certain medicines.

Patient can simply ask “Which food should I avoid to take with my medications?”

What is drug-food interaction?

Drug-food interaction is the reaction which occurs when your food/beverage and medicine interfere with one another.

Taking medicine at the very same time that you are taking your food may cause your body not to properly absorb the medicine you have just taken.

On the other hand, certain foods may delay or decrease the absorption of the drug, this is why some medicines should be taken on an empty stomach or perhaps one to two hours before eating.

Also, food/beverage can cause a reaction that changes the effect of the medicine or even prevent the action of the medicine. A good example for this is when a dairy product is combined with antibiotics like tetracycline, it forms a complex compound where there’s no absorption at all.

Another example is alcohol and drugs. Patients should always be wary of mixing any medication with alcohol, but some interactions are more serious than others.

For instance, ingesting alcohol while taking a prescription stimulant could cause the patient to not fully realise how intoxicated they are. This is especially true when the stimulant is being abused, but it can also happen when the patient takes the drug as prescribed.


Drug-food interaction can also create or heighten the side effects of the medicine taken but also some medicines are easier to handle when taken with food otherwise they would lead to more side effects like nausea, vomiting, dizziness and more of the side effects.

“Knowledge is needed in order to deal with all these possible drug-food interactions. Patient or those taking care of a patient must seek enough information about such interactions prior to taking their medicines,” says Mr Kauke Zimbwe, a clinical pharmacist based at Ocean Road Cancer Institute(ORCI).

“Healthcare professionals being the corner-stone of health information must provide all the information in such a way, which can easily be understood by patient(s).

It is much preferred that all patients with chronic diseases and those who occasionally use a certain medicine from time to time, must have a better understanding of their medicines, they have to be aware of possible drug-food interactions related to their routine medicines and other drug interactions as well,” Mr Zimbwe concludes.

In cases of any query, it is advisable to ask a pharmacist from a nearby community pharmacy or perhaps from any available health practitioner who is knowledgeable about medicines.

Some of the basic questions on drug-food interaction which any patient can ask, include:

• Which time is better to take my medicine?

• Could I take my medicine before, with, after food or on an empty stomach?

• What types of food must I avoid while taking my medicine?

• What happens if I eat certain foods with my medicine?

• Are there any other substances I need to avoid?

• Are there any other interactions I need to be concerned about?

Patients may not recognise or sometimes forget that even healthy foods can have severe consequences when mixed with certain drugs.

As medical experts, prescribers and dispensers should recognise their responsibilities to clearly communicate with their patients the risks of possible food-drug interactions for both prescriptions, over the counter medicines and home remedies.

The author is based at Catholic University of Health and Allied Sciences (Cuhas).