Getting to the Bottom of Chronic Cough

Julian Whitaker, MD

Do you have a cough you just can’t seem to shake? Whether it’s racking spasms that leave you red in the face and gasping for air, an irritating distraction that interferes with sleep or other activities, or just an annoying tickle in the throat that has to be “scratched,” chronic cough significantly impairs quality of life.

Let’s take a look at the usual—and some unusual, yet treatable—causes for this very common condition.

Respiratory Reasons for Coughing

Respiratory disorders such as asthma and chronic obstructive pulmonary disease (COPD) are the most obvious culprits in chronic cough. But you’d be surprised at how often these conditions are overlooked when symptoms are as “mild” as a persistent cough. Compounding the problem is the belief that asthma emerges only during childhood (in reality, it can come on at any age) and the fact that COPD is rarely diagnosed until 25–50 percent of lung function is lost.

A Brazilian study will give you an idea of how often these conditions are missed. Researchers recruited men and women with unexplained coughing of 8 to 540 weeks (over 10 years!) duration. Most of these people had been prescribed cough-suppressing drugs, yet no one had ever been able to figure out what was triggering their coughing.

Extensive evaluation revealed that 39 percent had previously undiagnosed asthma, and 11 percent had COPD. Another 11 percent had chronic upper airway cough syndrome (commonly called postnasal drip) related to allergic rhinitis, bacterial or fungal sinusitis, or another “-itis” (inflammation) of the sinuses or upper airways. Smaller numbers had lingering viral or bacterial infections, and a handful suffered with serious lung diseases such as cancer or tuberculosis. More than 90 percent of these patients responded well to appropriate treatment.

Control GERD, Eliminate Coughing

Coughing isn’t always initiated in the respiratory system. Another leading trigger is gastroesophageal reflux disease (GERD). This condition affects the lower esophageal sphincter muscle, which opens to let food and liquids pass into the stomach and closes to prevent backup of stomach contents. When this muscle becomes lax or weak, stomach acids flow back (reflux) into the esophagus. Although heartburn and indigestion are the signature symptoms of GERD, these strong acids can also cause difficulty swallowing, hoarseness, sore throat, and persistent cough.

If you discuss this with your physician, be prepared to get a prescription for a proton pump inhibitor (PPI) or other acid-suppressing drug. But before you agree to meds, I urge you to try a safe, inexpensive supplement called deglycyrrhizinated licorice (DGL). We use DGL at Whitaker Wellness to treat all types of gastrointestinal problems because it protects and regenerates the mucosal cells in the digestive tract. It is particularly effective for heartburn and GERD—and, in some cases, chronic cough as well. I had a patient whose constant cough and adult-onset asthma completely resolved after she began taking DGL.

Could It Be a Vitamin B12 Deficiency?

Another hidden problem that may contribute to chronic cough is sensory neuropathy. Damage to nerves in the larynx can lead to hypersensitivity and increased responsiveness to allergens, reflux, and other irritants. Fortunately, there is a solution: increasing levels of vitamin B12, which is required for optimal neurological function and is a well-documented treatment for neuropathies of all kinds.

In a study published earlier this year, Italian researchers tested 42 patients with chronic cough of unknown origin and found that 27 of them were overtly deficient in vitamin B12—and those who were deficient had significantly greater laryngeal hyper-responsiveness. All 42 patients were treated with B12 injections for two months. When they were retested, the cough thresholds in patients who had been vitamin deficient significantly improved, while there was little difference in those who initially had adequate B12 status.

If you have an unresolved cough, give vitamin B12 supplements (1,000 mcg daily) a try. There’s an erroneous belief that injections or sublingual tablets are the only way to raise blood levels of this vitamin, but oral B12 works just fine. It’s safe, well tolerated—and just might be the answer to your chronic cough.

Drugs Could Be the Problem

Finally, do not overlook the possibility that chronic cough may be iatrogenic, or inadvertently caused by medical treatment, in this case by drugs. ACE inhibitors, a popular class of medications for heart disease, hypertension, and heart failure, promote a chronic dry cough in one in four patients who take them—and it’s severe enough that a good percentage of them discontinue the drug.

Beta-blockers, also used to treat cardiovascular issues, are problematic as well, though to a much lesser degree. If you’re taking either of these meds, talk to your doctor about replacing them, preferably with side effect–free, nondrug therapies.

Recommendations

• The recommended doses of deglycyrrhizinated licorice (DGL) is one tablet chewed 20 minutes before meals. The suggested dose of oral vitamin B12 is 1,000 mcg daily.
• Look for these products in your health food store or order by calling (800) 810-6655.

References

• Bucca CB, et al. Unexplained chronic cough and vitamin B-12 deficiency. Am J Clin Nutri. 2011 Mar;93(3):542–548.
• Chung KF, Pavord ID. Prevalence, pathogenesis, and causes of chronic cough. Lancet. 2008 Apr 19;371(9621):1364–1374.
• Ribeiro M, et al. A prospective longitudinal study of clinical characteristics, laboratory findings, diagnostic spectrum and outcomes of specific therapy in adult patients with chronic cough in a general respiratory clinic. Int J Clin Pract. 2006 Jul;60(7):799–805.

Modified from Health & Healing with permission from Healthy Directions, LLC. Photocopying, reproduction, or quotation strictly prohibited without written permission from the publisher. To subscribe to Health & Healing, click here.