10 Medications You Should Never Take With Coffee

Most people in the world start the day with a cup of coffee; many also begin the day with medications. Studies show that coffee may quicken the process of moving food through your digestive system—which can affect your medications, too.

Drinking coffee at the same time you take your medication may alter how fast those are absorbed into your bloodstream. A group of researchers reviewed numerous medications and how coffee affected them. They reported that coffee “significantly affects the absorption, distribution, metabolism, and excretion of many drugs."  

Not all medications are affected by drinking coffee. People who take the following medications may benefit from changing the timing of their morning cup of coffee.

1. Thyroid Medicine

Hypothyroidism indicates that the thyroid gland (a butterfly-shaped gland at the front of your neck) is not producing enough thyroid hormone. This can cause weight gain, dry skin, joint pain, hair loss, and irregular menstrual periods.

Many people are prescribed levothyroxine or other medications to help balance out their hormones. Studies show that drinking coffee at the same time as taking your thyroid medication can reduce how much of your medicine is absorbed by your body, making the medicine less effective for you. And it’s not a small effect: Patient case reports show that coffee can even reduce the absorption of thyroid medicine by more than half.  

2. Cold or Allergy Medication

Medications for colds or allergies are used by millions of people, and they often contain central nervous system stimulants like pseudoephedrin. Coffee is also a stimulant, so washing your allergy med down with coffee may increase symptoms like restlessness and the inability to sleep. 

Some allergy meds, like fexofenadine should not be taken with coffee as it can overstimulate your central nervous system, increasing the symptoms of restlessness. It’s always a good idea to ask your healthcare provider for advice regarding the combination of coffee and cold or allergy medicine.

3. Diabetes Medication

If you mix your coffee with sugar or milk, that could lead to a spike in blood sugar and impact how well your diabetes medication works. In addition to that, studies show that caffeine may worsen symptoms for people with diabetes.

Drinking anything with caffeine, like coffee, could raise your insulin and blood sugar levels, according to a study published by the American Diabetes Association. The study was small, so more research is needed. Still, the researchers warned that drinking too much caffeine could make it more difficult to manage blood sugar and eventually raise the risk of diabetes complications. 

Diabetes and prediabetes are very common in the U.S. and other Western countries. According to the Centers for Disease Control and Prevention (CDC), over 37 million Americans have diabetes, and nearly 100 million have prediabetes. Most people don’t know they have it. With those numbers, it’s no surprise that millions of people take diabetes medications daily.

4. Alzheimer's Medicine

Alzheimer’s disease is the seventh leading cause of death in America and mostly affects people over the age of 65. It is a disorder of the brain that results in a loss of cognitive function, making it difficult to think, remember, or go about your daily tasks. Millions of Americans live with Alzheimer’s disease and take medication for  the condition.

Alzheimer’s medicine, like donepezil, rivastigmine, and galantamine are affected by caffeine. The caffeine in coffee tightens up the blood-brain barrier and can decrease how much of the drug makes it to your brain. Alzheimer’s medications work by protecting the neurotransmitter acetylcholine, and drinking high amounts of coffee has been shown to impair that protective effect. 

5. Asthma Medication

Asthma is a chronic disease that affects the lungs, inflaming and irritating the airways. This results in difficulty breathing, coughing and wheezing, and a tight feeling in the chest. Millions of people in the U.S., both adults and children, live with asthma and take medications for it.

Many people with asthma take bronchodilators, like aminophylline or theophylline, during a flare-up. Bronchodilators work by relaxing the airways, making breathing easier, but they come with side effects like headache, restlessness, stomach pain, and irritability. Drinking coffee or other drinks high in caffeine can increase your risk of these side effects. Coffee can also reduce how much of the medication is absorbed and used by your body.

6. Osteoporosis Medication

Osteoporosis makes your bones thin and fragile, increasing your risk of bone fracture. Millions of people have osteoporosis, though it’s most common in women, especially those who have already gone through menopause.

Drugs like risedronate or ibandronate prevent and treat osteoporosis. They should not be taken at the same time as coffee because it makes the drug less effective. It is recommended that you take these medications before eating or drinking anything and only wash the pill down with plain water. This will allow your body to maximize the full amount of the medication. When you drink coffee with these types of medications, their effectiveness can be reduced by more than half.

7. Antidepressants

According to the CDC, one in 10 teens and adults take antidepressant medications daily. They are the most prescribed drugs for adults in their twenties and thirties, and their use has increased dramatically over the last few decades. They can help with depression, a mood disorder that affects how you feel and function.

Coffee can affect how your body uses antidepressant medications. Some drugs, like fluvoxamine, amitriptyline, escitalopram, and imipramine can be metabolized differently if you drink coffee at the same time, especially large amounts of coffee. Coffee can reduce the amount of the medicine that is absorbed by your body.

Studies show that fluvoxamine, in particular, has been found to enhance the usual side effects of caffeine. This can cause symptoms like insomnia and heart palpitations. It’s best to take your medication and hold off on the coffee for a while.

8. Antipsychotic Medicine

Antipsychotic medicines are helpful for people who live with schizophrenia, mania, major depressive disorder, and other mental health problems. Nearly four million Americans use these medications each year. Antipsychotic medications work by inhibiting certain neurotransmitters or blocking receptors in the brain. 

Medications that treat psychosis include phenothiazine, clozapine, haloperidol, and olanzapine. Coffee can make your body absorb less of these medications than you normally would if you waited a while to enjoy your morning cup of coffee. Studies show that many of these medications are metabolized or broken down by the body differently in the presence of coffee. To get the full effect of your medicine, take it with water instead of coffee.

9. Blood Pressure Medicine

According to the CDC, tens of millions of Americans live with hypertension (high blood pressure). For many, it’s not well controlled. Hypertension increases your risk for heart disease and stroke. It’s a common but silent disease since it rarely shows symptoms.

Many people take blood pressure medications, like verapamil or propranolol, which work by slowing down your heart rate. That means your heart doesn’t have to work as hard to pump blood to all of your body’s cells.

However, drinking coffee at the same time as taking blood pressure medications like felodipine can cause less of the medicine to be absorbed by your body. You may not get the full benefit of the medicine. Talk with your healthcare provider about how to time your pills and your morning cup.

10. Melatonin

Melatonin is a natural hormone that your body makes which helps you feel sleepy at night. The hormone is triggered by the sun going down, signaling to your brain that it’s time to rest. Melatonin is also sold over-the-counter (OTC) in supplement form and is used as a sleep aid. 

By contrast, coffee works as a stimulant, making you feel more awake. The caffeine in coffee does the exact opposite job of melatonin. It can make you more alert and make it harder to fall asleep. Drinking coffee can inhibit melatonin production in your body and make the hormone less effective. If you take melatonin at the same time as drinking coffee, they could cancel each other out. 

When To See A Healthcare Provider

If you take any of these medications, and especially if it’s recommended that you take them first thing in the morning, try delaying your first cup of coffee.

If you take more than one medication, talk to your healthcare provider about how to balance out your pills and your coffee. If you are experiencing any unpleasant side effects, like restlessness, jitteriness, or insomnia, your healthcare provider can help you find a solution. 

A Quick Review

Coffee is a stimulant because of its high caffeine content. Between the stimulant effects and its effects on your gastrointestinal tract, coffee can alter how your body breaks down and absorbs your medications. You may just need to change the timing of your coffee break, but if you’re experiencing any symptoms, it’s always a good idea to reach out to your healthcare provider.

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