12 Medications You Should Never Mix With Coffee

Coffee contains caffeine, which can affect how your body absorbs and processes certain medications. If you take prescriptions, your healthcare provider may suggest avoiding coffee or separating when you drink it from when you take your meds.

1. Anticoagulants

Anticoagulants (blood thinners) are drugs that prevent or reduce blood clotting. People at high risk of blood clots usually take an anticoagulant medication daily. 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 may affect how your body absorbs antidepressant medication, which is used to treat depression, anxiety, and other mental health conditions. 

Drinking large amounts of coffee when taking antidepressants may reduce the amount of medication your body absorbs, lowering the medication’s effectiveness. Antidepressants that are altered by caffeine include:

• Amitriptyline

• Luvox (fluvoxamine)

• Lexapro (escitalopram)

• Tofranil (imipramine)

Taking Luvox with coffee may increase the risk of experiencing caffeine side effects like heart palpitations and sleep problems.

3. Antipsychotics

Antipsychotics are medications used to treat serious mental health conditions like major depressive disorder and schizophrenia. Taking these medications with coffee may cause the body to absorb less of the drug. 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 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 coffee or other 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 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 one 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 six cups of coffee daily may increase the risk of heart disease. More research is needed.

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 based on their healthcare provider's advice.