Medically reviewed by Sohaib Imtiaz, MD
Key Takeaways
Coffee can interfere with how your body absorbs or reacts to many common medications, including antidepressants, anticoagulants, and thyroid drugs.
Caffeine may increase the risk of side effects like restlessness, heart palpitations, or reduced drug effectiveness for several treatments.
People taking certain medications or with specific health conditions may need to limit or avoid coffee and other caffeinated drinks based on their healthcare provider’s advice.
Coffee can interfere with how your body processes certain medications and may lead to increased side effects or reduced effectiveness. If you take any of these medications, you may need to avoid coffee and other caffeinated drinks or drink them at different times of the day.
1. Anticoagulants
Anticoagulants (blood thinners), help prevent or reduce blood clotting. They are often prescribed daily for those at high risk of clots. Common examples include Jantoven (warfarin) and heparin.
Research shows that caffeine increases the concentration of blood-thinning medication in the bloodstream, enhancing its effects. People who consume caffeine regularly while taking anticoagulants may be at risk of bleeding.
2. Antidepressants
Coffee can impact the absorption of antidepressants, which are used to treat depression, anxiety, and other mental health issues.
Drinking coffee and other highly caffeinated drinks at the same time as taking certain antidepressants may reduce or increase the amount of medication your body absorbs, lower the medication’s effectiveness, or increase or reduce the effect.
While it is unclear how much caffeine is required to produce these effects, consuming 2 or 3 cups of coffee a day should not cause drug interactions. Since not all antidepressants are affected by caffeine, talk with your healthcare provider for specific instructions.
Antidepressants that are altered by caffeine include:
- Amitriptyline
- Luvox (fluvoxamine)
- Prozac (fluoxetine)
- Lexapro (escitalopram)
- Imipramine
- Paxil (paroxetine)
Taking Luvox with coffee may increase the risk of experiencing caffeine side effects like heart palpitations and sleep problems.
3. Antipsychotics
Antipsychotics treat serious mental health conditions such as major depressive disorder and schizophrenia. Consuming coffee with these medications may reduce their absorption. Examples include:
- Abilify (aripiprazole)
- Compro (prochlorperazine)
- Haldol (haloperidol)
- Orap (pimozide)
It is likely safe to drink coffee while on antipsychotic medication as long as you spread out your dosage and cup of coffee.
4. Asthma Medications
Asthma is a condition that affects the lungs and airways, resulting in trouble breathing, chronic cough, and wheezing.
Bronchodilators are asthma drugs that relax the airways and make breathing easier. Side effects of the medication include restlessness, racing heart, headache, and irritability.
Caffeine can worsen these side effects and reduce the amount of medication your airways can absorb. Avoid drinking coffee when you need to use a bronchodilator.
5. Blood Pressure Medication
High blood pressure (hypertension) is a common chronic health condition in the United States. When left untreated, hypertension can lead to heart disease and stroke.
Blood pressure medications like Inderal (propranolol) and Lopressor (metoprolol) work by lowering your heart rate and reducing the strain on the heart. Drinking coffee at the same time you take blood pressure medication may cause your body to absorb less of the drug.
6. Cholinesterase Inhibitors
The caffeine in coffee has serious effects on medications for Alzheimer’s disease and dementia called cholinesterase inhibitors. Alzheimer’s medicines like Aricept (donepezil) work directly on the brain and help protect the neurotransmitter acetylcholine.
Drinking coffee with these medications lessens their effectiveness. Caffeine decreases how much of the medication reaches the brain.
7. Cold and Allergy Medications
If you regularly take medication for allergies or cold symptoms, check if they contain pseudoephedrine. This medication is a nervous system stimulant and has many of the same effects as coffee.
Taking pseudoephedrine with coffee may increase the risk of side effects such as restlessness, heart palpitations, and trouble sleeping. Do not drink coffee when taking Sudafed (pseudoephedrine) or Allegra (fexofenadine).
8. Diabetes Medication
Research shows that caffeine may worsen diabetes symptoms and interfere with glucose control. Drinking a lot of caffeine could raise your levels of blood sugar and insulin (the hormone that regulates blood sugar). Drinking too much coffee could make it more challenging to manage your diabetes.
9. Methotrexate
Methotrexate is an immunosuppressant drug often used in cancer treatment (chemotherapy). Caffeine affects how the body absorbs methotrexate, so drinking coffee while taking it may cause higher levels in the bloodstream.
10. Osteoporosis Medication
Osteoporosis occurs when bones lose mineral density and mass, becoming thin and fragile. Osteoporosis medications like Boniva (ibandronate) and Actonel (risedronate) strengthen bones and reduce fracture risk.
Drinking coffee and other highly caffeinated drinks with these drugs affects their absorption and may make them less effective. Most healthcare providers recommend taking osteoporosis medications without food or drink (other than water).
11. Quinolone Antibiotics
Quinolone antibiotics like Cipro (ciprofloxacin) treat bacterial infections. When taken with caffeine, quinolone antibiotics can enhance caffeine’s effects and increase the risk of side effects like heart palpitations and restlessness. Avoid drinking caffeinated beverages when taking this antibiotic.
12. Thyroid Medications
Thyroid medications work by regulating the amount of thyroid hormone in the body. People with hypothyroidism have low levels of thyroid hormone because the thyroid gland is not producing enough.
Drinking coffee with thyroid medications like Synthroid (levothyroxine) can reduce the medication’s effectiveness. Caffeine lowers your body’s ability to absorb thyroid medication by half.
Speaking With a Healthcare Provider
If you are taking any of the medications listed above, ask your healthcare provider if you should limit your coffee and caffeinated beverage intake. They may recommend changing the time that you drink coffee or take your prescriptions, or they may also recommend avoiding coffee while taking the medication.
Your pharmacist is also a helpful resource. If you take several medications, ask your pharmacist how they interact with each other and if coffee is safe for you.
Who Should Avoid Coffee?
For some people, avoiding coffee is the healthiest choice. Coffee has not been proven safe for the following groups of people:
- Children and adolescents: Too much caffeine may cause heart palpitations, sleep problems, and anxiety in children and teens.
- Pregnant people: Large amounts of caffeinated coffee may raise the risk of preterm birth and miscarriage. It can also cause nausea and sleep problems. Many healthcare providers recommend consuming less than 200 milligrams (about 1 cup of coffee) daily during pregnancy.
- People with anxiety: Caffeine can exacerbate (worsen) anxiety symptoms and cause sleep issues and high blood pressure.
- People at risk of heart disease: Drinking more than 6 cups of coffee daily may increase the risk of heart disease. More research is needed.
Read the original article on Verywell Health