Everyone is in a hurry these days. This is especially true when it comes to prescriptions. Many doctors don’t even hand you a paper prescription; they just transmit it electronically from their computer or smart phone directly to the pharmacy. Unless you ask, the prescriber may not tell you anything about food and drink that could change absorption of the pill.
If you hang out at the pharmacy for a few minutes, you will discover that most people grab and go as soon as they swipe their card. Rarely do patients take time to find out how to take their medicine by asking detailed questions of their physician or pharmacist.
How Should You Take Your Medicine?
The trouble with the rush-rush approach to medications is that people may not learn how food and drink could affect their pills. Grapefruit offers the best-known examples of potentially dangerous drug-food interactions.
Grapefruit Juice Affects Drugs:
An article in the Canadian Medical Association Journal (online, Nov. 26, 2012) revealed that 85 different drugs might be incompatible with grapefruit. We first learned about this unusual interaction in 1991 (Lancet, Feb. 2, 1991). Researchers in Canada were testing the blood pressure pill felodipine (Plendil) and discovered quite by accident that grapefruit juice tripled the amount of felodipine in the blood compared to water or orange juice. The increased blood levels led to symptoms such as headaches, lightheadedness and flushing.
At first, many health professionals found this idea laughable. But when problems arose with other medications such as the transplant drug cyclosporine (Neoral, Sandimmune) and cholesterol-lowering drugs such as atorvastatin (Lipitor) and simvastatin (Zocor), they had to take grapefruit incompatibilities seriously.
What Does Grapefruit Do?
Grapefruit compounds slow down enzymes (CYP3A4) in the lining of the intestine that normally process the drugs and speed them on their way. This can lead to elevated levels of medicines and cause unintentional overdosing.
Medications that are affected include the blood pressure pill nifedipine, the anti-cancer medicine docetaxel (Taxotere) and the narcotic pain reliever oxycodone. People who would like to know more about how food and drink affect medicines may be interested in our Guides to Food, Drug and Grapefruit Interactions.
Other Drug Interactions with Food and Drink:
Grapefruit is not the only problem. Taking aliskiren (Tekturna) to lower blood pressure with apple juice may reduce the blood levels significantly and reduce the effectiveness of the medicine.
Levothyroxine taken to treat a sluggish thyroid gland can be affected by calcium, iron and magnesium. In addition, multivitamins and juices that are fortified with calcium may interfere with the absorption of this hormone as well as that of several antibiotics (ciprofloxacin, norfloxacin and tetracycline). Unfortunately, people who take their thyroid hormone with coffee do not absorb it as well (Thyroid, March 2008).
Hot Coffee May Speed Drug Absorption:
Q. Years ago, my doctor prescribed 800 mg of ibuprofen three times a day. I was waiting for spinal laminectomy surgery due to a herniated disk.
My stomach began to ache, and I was worried about developing an ulcer. This may sound crazy, but I noticed the GI irritation was always less when I took ibuprofen with hot coffee.
Is it possible that taking pills with a hot drink reduces damage to the GI tract and assists with dissolving and absorption? If I think of simple things such as washing dishes, it is harder and takes longer if the water is cold.
The Puzzle of Beverage Temperature:
A. You raise a fascinating question that has not been well studied. Does beverage temperature impact drug absorption?
A small study of acetaminophen (Tylenol) demonstrated that a hot drink resulted in faster and greater drug absorption (Pharmaceutical Research, Aug. 2014). Lab tests showed tablets disintegrated almost three times faster in warm liquids than in cool ones (European Journal of Pharmaceutical Sciences, Aug. 1, 2020).
The caffeine in your coffee might also have an effect. Caffeine can increase pain relief from NSAIDs such as ibuprofen (Pharmaceuticals, May 11, 2023). An objective review from the Cochrane Collaboration concluded that “taking a single 200 mg ibuprofen tablet with a cup of modestly strong coffee or caffeine tablets…” could provide good pain relief at lower doses of ibuprofen (Cochrane Database of Systematic Reviews, July 14, 2015).
Take Your Pills with Enough Water:
Even the amount of water you swallow when taking your pills may matter. The antibiotics erythromycin and amoxicillin work best when swallowed with a full 8 ounces of water. That’s why it makes sense to get explicit instructions any time you are given a prescription.
