Cold and Flu Medicines: What Do Thyroid Patients Need to Know?

Many packages of over-the-counter cough medicines and decongestants say "Do not take if you have one of the following..." and then go on to list thyroid disease. You may wonder, then, if you can take these products for your cold or flu symptoms?

The reason for these thyroid-specific warnings is mainly due to a key ingredient: pseudoephedrine.  Found in some formulations of Sudafed and some cold and allergy medicines, pseudoephedrine is a stimulant and can be dangerous to people with active hyperthyroidism. Pseudoephedrine can strain an already over-taxed heart, or raise your blood pressure, worsening two common hyperthyroidism symptoms.  

Many cold and flu remedies contain other decongestants that can narrow your blood vessels and reduce nasal swelling as a way to help reduce your stuffiness. But the narrowing can affect all of your blood vessels, which in turn raises your blood pressure. This effect is not recommended if you are hyperthyroid.

Hypothyroidism—an underactive thyroid—is the far more common thyroid condition in the United States. If you are hypothyroid, can you take these types of medicines?

There is no official consensus, but generally, it is not recommended that people with any thyroid condition take products with pseudoephedrine, or the natural version, ephedra, which used to be found in diet and weight loss over-the-counter supplements. There are anecdotal reports of people with thyroid disease becoming overly sensitive to stimulants like caffeine, pseudoephedrine or ephedra.

As far as over-the-counter medicines, you might want to ask your doctor about using a product like Coricidin HBP, a cold remedy made especially without stimulating ingredients. You should also be be able to safely take most other decongestants, or pain relievers such as aspirin, acetaminophen or ibuprofen to help with fever, aches, or a sore throat. Again, check with your healthcare provider to ensure that these options are safe for you. 

A saline—not decongestant—nasal spray can sometimes help relieve sinus congestion or a stuffy nose. 

You can also consider trying some of the natural suggestions described below. 

There are a number of alternative remedies that may help that you can try to help with cold and flu-related symptoms.

Noted alternative practitioner Andrew Weil, MD and Prevention magazine both suggest vitamin D, echinacea and the herb astragalus—among other natural remedies—to help boost the immune system during flu season.

Some research has also found that ginseng may help reduce the incidence or duration of flu, cases of flu, and raise the activity rate of your immune cells that fight infections.

There are a number of other natural, botanical, and supplement-based approaches that may be helpful for relief of your cold and flu symptoms, or help shorten the duration of your illness. These include the following:

• Elderberry: Elderberry apparently works by strengthening the cell membrane so a virus cannot penetrate it. It also appears to inhibit the enzyme that viruses use to weaken the membrane. Verywell's Alternative Medicine guide has more information on elderberry.
• Vitamin C: Though the recommended daily dosage of vitamin C is usually no higher than 100 mg/day, some experts believe that taking as much as 1 to 6 grams (1000 - 6000 mg) of vitamin C per day may be helpful during illness, especially viral illnesses. Some studies have shown that higher-dose vitamin C may help reduce the duration of a flu virus. The suggested dosage would be to take 1000 mg of vitamin C every 2 hours unless diarrhea or gas occurs.
• Zinc Lozenges: Over-the-counter zinc lozenges, if taken at the onset of your cold and flu symptoms, may help reduce the symptoms of your flu or cold, and shorten the duration.
• Oscillococcinum: This homeopathic treatment may help with flu symptoms, particularly when taken right away after the onset of symptoms.

Don't forget the basics to help prevent you from getting a cold or the flu: regular hand washing, healthy eating, sleep, and regular exercise. You may also want to discuss a flu vaccine with your health care provider.