Because food-drug interactions occur very often and have adverse effects on the drug's efficacy, you really need to pay heed to your pharmacist's instructions.

While food and medicine are things we need in life and for good health, they sometimes do not mix well.

Apart from preventing a drug from working the way it should, a food-drug interaction can also make the side effect from a drug better or worse or even cause a new one altogether.

Probably the most common warning ever heard was not to take alcohol if under medication. This is because alcohol, whether taken before, after or with a medication, has very adverse effects on the medicine and on the body itself.

Taking drugs that cause drowsiness while still taking alcohol can increase it thus reducing functionality and even causing accidents in the process. Some drugs like acetaminophen (pain reliever) have effects on the liver and when taken with alcohol they enhance these effects and cause liver damage.

Some medications, including pain relievers like ibuprofen, aspirin and diclofenac should be taken with food since they may upset your stomach.

On the same note, there are those that should not be taken with food since it delays or reduces their absorption. These interactions are common with some anti-retro viral drugs and antimycobacterials (TB drugs).

Caffeine frequenters should also take it cautiously when under medication. This is because it might interfere with efficiency of drugs.

Above all, pay careful attention to your doctor or pharmacist's instructions and if you aren't sure of something, ask!