Medications That Don't Mix Well with Coffee

By Dr. Scott Olson, ND Posted May 15, 2025

If you’re a regular Living Well Daily Reader (and I certainly hope you are), I probably don’t need to tell you I’m a coffee fan.

I regularly share information on coffee’s many health benefits—from boosting metabolism to reducing disease risk.

But many don’t realize that cup of Joe can interact with common medications, sometimes reducing their effectiveness by more than half.

Are you taking one of them?

Coffee is delicious. And when you don’t load it up with sugar and a gallon of cream, it has a bunch of health benefits.

But if you’re taking certain medications, your favorite morning brew could interact with them.

Let me walk you through some of the most concerning interactions I see:

• Thyroid Medication: If you take levothyroxine with your coffee, you could be absorbing less than half of your prescribed dose—meaning less medication actually gets into your bloodstream to do its job. Caffeine speeds the movement of the drug through the digestive system. This can leave you feeling fatigued, gaining weight, and experiencing other hypothyroid symptoms despite taking your meds. Take thyroid medication with plain water at least 30-60 minutes before your first cup of coffee.

• Blood Pressure Medications: The absorption of hypertension drugs like felodipine and verapamil can be reduced with coffee. Even more concerning, the stimulant effect of caffeine can counteract the intended effect of medications like propranolol that are designed to slow your heart rate. If you’re on any of these meds, discuss your caffeine consumption with your doctor.

• Diabetes Medications: The relationship between coffee and diabetes drugs is complex. Adding a lot of sugar or cream to your coffee could cause blood sugar spikes. But in some cases, even black coffee can work against your meds, temporarily increasing insulin and blood sugar levels. Remember that research has also found that coffee benefits diabetics by reducing blood sugar and medication needs. So, if you aren’t experiencing blood sugar spikes, and your doctor approves, go ahead and enjoy your Java.

• Osteoporosis Medications: Drugs like risedronate or ibandronate can lose more than half their effectiveness when taken with coffee. For these meds to work correctly, take them with water first thing in the morning, then wait at least 30 minutes before coffee.

• Alzheimer’s Medications: Caffeine tightens the blood-brain barrier (the protective filter that controls what substances reach the brain) and may reduce the amount of drugs like donepezil, rivastigmine, and galantamine that reach the brain.

• Antidepressants: Coffee can alter the metabolism of medications (how quickly your body processes and eliminates them) like fluvoxamine, amitriptyline, and escitalopram, increasing their side effects, such as insomnia and heart palpitations.

• Antipsychotic Medications: Studies show that drugs like clozapine, haloperidol, or olanzapine are metabolized more quickly when taken with coffee, potentially reducing their effectiveness.

• Asthma Medications: Some studies suggest coffee’s bronchodilating properties (its ability to open up airways in the lungs) might help with asthma symptoms. However, combining coffee with bronchodilating drugs like aminophylline or theophylline could increase the risk of side effects like headaches, restlessness, and stomach pain.

• Cold or Allergy Medications: Some over-the-counter allergy and cold remedies contain stimulants like pseudoephedrine. When combined with the caffeine in coffee, these drugs can cause uncomfortable jitters, anxiety, or insomnia.

In most cases, these coffee and drug interactions aren’t particularly dangerous, but they could reduce the effectiveness of some prescriptions.

On the other hand, studies show that coffee has lots of benefits. Your favorite morning brew can boost heart health, fight memory loss, and improve metabolism.

So, what’s the bottom line?

Check with your healthcare provider about any potential interactions with coffee or caffeine. And should you decide to continue drinking coffee, for most medications waiting one to two hours before drinking coffee can minimize interactions.

P.S. Could THIS type of coffee destroy diabetes?!

Written By Dr. Scott Olson, ND

Nearly 25 years ago, failed mainstream medical treatments left Dr. Olson in constant pain – and his health in ruins. And that’s when he did something REVOLUTIONARY. He began his career in medicine – and dedicated his life to uncovering the true, underlying causes of disease.
Through his innovative medical practices in Tennessee and Colorado, Dr. Olson has helped cure countless seniors from across America of arthritis… heart disease… diabetes… and even cancer. All without risky prescription drugs or painful surgeries.

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