How food and beverage interfere with your medications

How food and beverage interfere with your medications (2)

How food and beverage interfere with your medications (2)

In “How food and beverage interfere with your medications (1),” the mechanisms how food and beverage ingredients either strengthen or weaken the medicine’s efficacy under the following conditions were explained.

  • Affecting the medicine to be absorbed.
  • Affecting the enzyme that metabolizes medicine.
  • Combining with the same or opposite ingredient of medicine.

This article will explain the efficacy may be influenced by the timing of taking medicine and meal, also when taken with nonessential items such as cigarettes or liquor.

Be careful of excess efficacy of medicine while on diet

When medicine which was taken from your month enters the stomach, it goes around the body with blood. The part of medicine combined with protein, the efficacy loses its result. On the other hand, the only part of medicine which didn’t combined with protein works at diseased spot. In short, the amount of protein within blood affects the medicational efficacy.

When a body is in malnutrition condition, the protein in blood decreases. The amount of medicine that does not get combined with protein increases, and both the efficacy and the risk of dangerous side effect becomes high.

Timing of medicine to be effective varies with the amount of meal you take

Medicines pass through stomach quickly and get absorbed on people who have small appetites, eat excessively little amount while on diet, or skip meals often. With this reason, the efficacy of medicine appears quickly but works too much, or dangerous side effect may occur.

In contrast, food in stomach bothers with medicine to be absorbed on people with big appetites or who snack a lot between meals.

Leave some time when eating incompatible food with your medicine

As explained in “How food and beverage interfere with your medications (1),” there are some unsuitable foods for medicines. When having these foods, leave some time before taking the medicine in order to avoid the ingredients from meeting in a stomach. However, the length of time remaining in a body varies with medicine.

In general, the medicines, which are taken 3 times a day, stay within a body short period of time. Is is considered to be safe as long as you take more than 2 hrs.(*)  interval.

*Each meal normally takes about 2 hours to be digested.

However, digestion often takes more than 2 hours when having the greasy food such as below. When having the food that is incompatible with medicine, it is necessary to leave long enough time until you take the medicine.

Meats: BBQ, Steak, Fried chickens, etc.

Staple food: Japanese ramen noodle, Fried rice, or any other pan-fried noodles, etc.

Even if you leave the enough time before or after taking medicine, on the other hands, there are foods that are unavoidable from the influence against medicine. For instance, grapefruit juice works to reduce the metabolic enzymes within river and strengthen the efficacy of medicine. Some reports say this effect lasted for 3 days after drinking grapefruit juice. There are foods that are not clearly defined how long you need leave time before taking medicines. Please receive a consultation from your doctor or pharmacist.

It is safe to have anything if you are not taking any medicines for internal use?

Among the medicines for external use such as ointment or nasal spray do not get influence from the food. It is because the ingredients of medicine do not go through a stomach or river and do not combined with the ingredients of food. The medicines applied via patch, injection, or a part of suppositories, however, interact with the ingredients of food or beverage within blood, thus the side effect may occur.

The medical patch for heart disease is one of the examples of this case. If having an alcohol beverage when medical patch is applied, a dangerous side effect may occur. If you use the medical patch for your heart disease, please get a confirmation with your doctor or pharmacist.

Alcohol and cigarette weaken the efficacy of medicine

Medicational efficacy does not work for smokers due to the function of tar which contains the composition that increases the amount of metabolic enzyme in a river and urges metabolizing medicine. Thus, the amount of medicine prescribed needed to be increased for smokers.

We need to be careful when trying to quit smoking as well. Enzyme decreases as a result of smoking cessation, and the targeted efficacy becomes stronger as well as the side effect.

For heavy alcohol drinkers, the effects are more complex and varies from efficacy to be weaker to stronger. It may affect the brain and consciousness to be dull or numb as a result of synergistic effect with medicine.

Chinese medicine and supplements are not the exception

So far, the effects of food, beverage, alcohol, and cigarettes on the efficacy of Western medicine had been commented mainly. Other than the Western medicine, we need to be careful with the traditional Chinese medicine and supplement on the compatibility with food and beverage.

Some say, “Chinese medicines are safe without side effects.” It is a false belief of Chinese medicine. The risk against body is not determined by whether it is artificial or natural. Many of Western medicine manufactured in factories also use the substances found in nature. It is not rare, in fact, that people suffer from side effects when taking both Western and Chinese medicines together.

Among the Chinese medicines, there is dangerous combination with food. It is same with the nutritional drinks that contains Chinese herbal extracts or herbal supplements. We need to remember any ingredient can turn into a poison depending on how you take them.


In this article, we have talked about the medicational influence of interval in between meals, and interaction with alcohols and cigarettes. We hope you understand how food or beverage affects the efficacy of medicines with this article and “How food and beverage interfere with your medications (1).” From next time, we will discuss about more detailed effects of each food on medicines.

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