Certain medications can have adverse interactions when taken at the same time you drink coffee. For instance, antipsychotic drugs like clozapine can have their effects reduced when consumed with caffeine. Similarly, certain antidepressants, especially MAO inhibitors, can lead to dangerous spikes in blood pressure when combined with caffeinated beverages. Ask your healthcare provider if caffeine could affect your medication.
Here are some more cautionary examples:
• Anticoagulants. Anticoagulants (blood thinners) are designed to prevent blood clotting. Research has found that coffee increase the concentration of the medication in the bloodstream, putting people who consume coffee regularly while taking anticoagulants at risk for bleeding, says Verywell Health.
• Asthma medications. Bronchodilators are asthma drugs that help relax airways to make breathing easier. Caffeine has been found to worsen the side effects of the medication such as restlessness, racing heart, headache and irritability.
• Blood pressure medication. Certain blood pressure medications, such as beta-blockers, can have their effectiveness impacted by caffeine. Caffeine can lead to an increase in blood pressure, counteracting the medication's intended effect of lowering blood pressure. This can make it more difficult to manage hypertension and maintain stable blood pressure levels, says Healthline.
• Cholinesterase inhibitors. Medicines that treat Alzheimer’s disease and dementia can be significantly affected by caffeine. Drugs like Aricept work directly on the brain to help protect the neurotransmitter acetylcholine. Caffeine decreases the amount of medicine that reaches the brain.
• Cold and allergy medications. If you regularly take medication that contains pseudoephedrine, which is a stimulant, consuming coffee with the drug may increase feelings of restlessness, heart palpitations, and trouble sleeping. Do not drink coffee when taking pseudoephedrine (Sudafed) or fexofenadine (Allegra) says Verywell Health.
• Diabetes medication. According to the Mayo Clinic, if you have diabetes, caffeine might affect the way your body uses insulin. And that could lead to higher or lower blood sugar. For some people with diabetes, about 200 milligrams of caffeine can cause this change. For others, it may have no significant effect on blood sugar. Caffeine affects each person differently. If you have diabetes, or if you find it hard to control your blood sugar, limiting the amount of caffeine in your diet might be helpful.
• Thyroid medication. Drinking coffee with thyroid medications like levothyroxine (Synthroid) may reduce the effectiveness of the medication. Caffeine lowers your body’s ability to absorb the medication by half. Waiting 30 to 60 minutes after taking thyroid medication before drinking coffee is the standard recommendation if you’re a coffee drinker. Some newer levothyroxine liquid formulations may be less sensitive to coffee’s interference. However, you may want to check with your prescribing doctor.