3 Types of Cold Medications That Don’t Mix Well With Coffee

When you’re sick with a cold or the flu, a hot cup of coffee might feel extra comforting, or it may simply be part of your normal morning routine. However, drinking coffee while taking certain cold and flu medications can worsen side effects.

1. Oral Decongestants

Caffeine is a stimulant. Stimulants increase nervous system activity and can increase heart rate, breathing rate, and alertness. Oral decongestants, such as pseudoephedrine (found in Sudafed), have stimulant-like effects, too.

Combining two stimulants—caffeine and an oral decongestant—can have additive effects. Doing so may cause:

Additionally, research has shown that combining caffeine with pseudoephedrine can increase blood sugar (which is especially a concern for people with diabetes) and body temperature.

Examples of medications to avoid mixing with caffeine include:

• Sudafed (pseudoephedrine)
• Sudafed PE (phenylephrine)
• Allergy medications that contain a decongestant, such as Claritin-D (loratadine/pseudoephedrine) and Allegra-D (fexofenadine/pseudoephedrine)
• Combination cold and flu medicines, such as NyQuil Severe Cold & Flu

Oral decongestants may not be appropriate for everyone, especially those with certain health conditions like:

Check with a healthcare provider before using an oral decongestant to ensure it is safe for you. If you do take an oral decongestant, it is a good idea to limit or avoid caffeine while taking it.

2. Cough Suppressants

Dextromethorphan is a cough suppressant that acts on the brain to reduce coughing. It is found in over the counter (OTC) and in some prescription cough medicines.

Some of the side effects of dextromethorphan include:

• Dizziness
• Lightheadedness
• Nervousness
• Restlessness
• Nausea

Because caffeine is a stimulant and can cause similar effects, it may worsen some of these side effects when taken at the same time. Examples of OTC drugs that contain dextromethorphan include:

• Delsym (dextromethorphan)
• Robitussin DM (guaifenesin/dextromethorphan)
• Mucinex DM (guaifenesin/dextromethorphan)

It’s best to check with a healthcare provider before taking any drug containing dextromethorphan, as it is not appropriate for everyone and requires caution in certain health conditions or with other medications. If you do take this medicine, consider limiting or avoiding caffeine.

3. Certain Allergy Medications

First-generation antihistamines, such as Benadryl (diphenhydramine), act a little differently in the body than newer antihistamines like Claritin (loratadine) and Xyzal (levocetirizine).

All antihistamines help relieve allergy symptoms like a runny nose and sneezing. However, first-generation antihistamines can also cause drowsiness, sedation, and fatigue, which can affect alertness, concentration, and memory. In some cases, they may even cause excitement or restlessness.

The caffeine in coffee may interfere with the sedating effects of first-generation antihistamines or worsen side effects like dizziness and restlessness. This can make it harder to tell how drowsy or impaired you are.

It is a good idea to limit or avoid caffeine while taking cold or flu products that contain a first-generation antihistamine. Examples of first-generation antihistamines include:

• Diphenhydramine
• Nighttime cold or flu products that contain diphenhydramine, doxylamine, or chlorpheniramine, such as NyQuil