What Thyroid Patients Need to Know About Decongestants

Decongestants can pose a risk to people living with a thyroid disorder, such as an overactive thyroid (hyperthyroidism) or an underactive thyroid (hypothyroidism).

This is because ingredients like pseudoephedrine can affect the blood vessels throughout the body. Some drugs may interact with your thyroid medication. And while there are many over-the-counter (OTC) drugs available for treating nasal congestion caused by a cold or seasonal flu, some can do more harm than good.

This article explains why some decongestants should be avoided and why it's important to discuss medication use with your healthcare provider before taking them.

Decongestants and Heart Health

Several types of decongestants work by causing the blood vessels in the linings of the nasal passages to contract and narrow. This decreases blood flow to the lining of the nose and sinuses, thereby reducing congestion and the production of mucus.

The catch is, this effect isn't limited to nasal passages: Blood vessels throughout the body are affected, which can be dangerous for someone with a thyroid condition. That's because both hyperthyroidism and hypothyroidism can affect the heart and circulatory system.

The decongestant most likely to be problematic is pseudoephedrine, which is sold not only as a single-ingredient medication, but is found in multi-symptom cold, flu, and allergy remedies as well. (Note that because pseudoephedrine has been used illegally to make methamphetamine, it is sold from behind the pharmacy counter.)

Less potentially problematic, but still important to be aware of, is phenylephrine. It is a weaker cousin of pseudoephedrine, used as a substitute for it in many OTC products. (However, it's so weak that it's no longer considered effective when taken by mouth.)

These decongestants show up in many products, and some brands have products that contain both ingredients. It's important to read labels so that you know what you're taking.

These lists represent a small sample of the many OTC medications that have pseudoephedrine or phenylephrine, alone or in combination with other ingredients.

Phenylephrine is also an active ingredient in some nasal sprays for treating congestion. Although the drug is targeted at blood vessels in the lining of the nose, experts don't know for sure that it won't affect vessels throughout the body.

You should check with your healthcare provider before using a nasal spray (such as Neo-Synephrine) if you have hyperthyroidism. The same may be true for nasal sprays containing oxymetazoline. These include:

• Afrin
• Anefrin
• Dristan
• Mucinex
• Nostrilla
• Vicks Sinex
• Zicam

Interactions With Thyroid Medications

Hypothyroidism is managed with a synthetic form of thyroxine (T4) called levothyroxine, available under the brand names Synthroid or Levothroid.

People may be at increased risk of cardiovascular side effects if they take pseudoephedrine or phenylephrine and levothyroxine. This could be especially dangerous for someone who has preexisting heart disease.

Alternatives to Decongestants

People living with a thyroid condition have options to relieve nasal congestion from a cold or flu without medication. You can:

• Try a nasal dilator that widens nasal passages, such as Breathe Right strips
• Rinse your sinuses with a sterile saline solution (using a neti pot)
• Use a saline spray or drops to thin mucus and make it easier to expel when you blow your nose
• Run a humidifier in the room where you spend the most time
• Take a warm shower or sit in the bathroom with the shower running hot enough to steam up the room
• Try herbal remedies, including lemon grass or rosemary

Acupuncture and acupressure may also help to relieve congestion.

If none of these strategies work, check with your healthcare provider to find out if there are other ways to get relief.

Summary

Some decongestants can pose a risk to people living with certain health conditions, including a thyroid disorder. This is because ingredients in over-the-counter (OTC) products, like pseudoephedrine, can affect the heart and blood vessels. Some products also may interact with your thyroid drugs.

Be sure to discuss the use of any OTC medication with your healthcare provider before you try them. You also may wish to consider natural remedies, like using a humidifier, before you try a nasal decongestant drug.