If you faint because of whooping cough, you may injure yourself.
Pertussis, or whooping cough, is a highly contagious respiratory disease that is particularly serious in infants. People of all ages can be infected by Bordetella pertussis, the bacterium that causes whooping cough. In young and elderly people, pneumonia is the most common -- and sometimes fatal -- complication of pertussis. Even in people who do not develop life-threatening complications, the forceful coughing associated with whooping cough can cause other problems, such as urinary incontinence, hernias, rib fractures and fainting, also called syncope.
Variable Signs and Symptoms
Whooping cough is typically characterized by repeated episodes of 5 to 10 forceful coughs, followed by a hurried inhalation of air -- the characteristic вЂњwhoopвЂќ of pertussis. Not all people with pertussis have these classic symptoms. Infants younger than 6 months old may have a slowed heartbeat, interrupted breathing and low blood oxygen levels. Older children, adolescents and adults typically develop the classic spells of coughing and whooping, but many teens and adults simply have a chronic, nagging cough. Syncope most often occurs during coughing spells.
Interrupted Blood Flow
Your brain is a metabolically active organ that requires a constant supply of nutrients and oxygen. If the blood flow to your brain is stopped for more than a few minutes, it can be irreversibly damaged. During shorter periods of reduced flow, your brain doesn't function well, and fainting may be the result.
A study published in the January 2013 issue of "BMC Neurology" demonstrated that forceful coughing temporarily disrupts your brain's blood flow and sets the stage for cough syncope. When you cough, the pressure within your chest increases and the blood returning to your heart from your brain is momentarily pushed back toward your brain. This transmits back-pressure to the arteries carrying blood into your brain, resulting in a reduction in blood flow. For certain people, this may trigger presyncope -- blurred vision, wooziness and lightheadedness -- or outright fainting.
Not everyone who has coughing spells associated with whooping cough experiences cough syncope. Factors, such as your age, sex and state of health, influence your susceptibility to passing out. The authors of the 2013 "BMC Neurology" article report that people with higher levels of endothelin-1 in their bloodstream are more likely to experience cough syncope. ET-1 is a protein that constricts your blood vessels, so elevated levels could reduce blood flow to your brain during coughing spells. People with chronic lung disease tend to have higher ET-1 levels and are more susceptible to cough syncope.
Risk for Injury
You may suffer injuries if you have cough syncope due to whooping cough, particularly if you lose consciousness while driving or performing other potentially hazardous activities. In the elderly, falls associated with cough syncope can result in hip fractures or bleeding within the brain. Notably, a 2013 review in "BMC Infectious Disease" showed the incidence of whooping cough is increasing among older Americans. Recent changes in vaccination policies -- a booster vaccination is now recommended for adults -- may reverse this trend.
When to Seek Help
If you have a severe cough that causes fainting or near-fainting, see your doctor for an evaluation. Once you've started coughing from pertussis, antibiotics and other medications may not help much. Your doctor will want to rule out other causes of cough or syncope and may recommend time off work or other measures to prevent injury.
If you have been exposed to someone with a forceful, repetitive cough and begin to develop coldlike symptoms yourself, see your doctor as soon as possible. Antibiotic treatment is not needed for common colds, but it can shorten the duration and reduce the severity of whooping cough if the medications are started early. Your doctor will determine if you need antibiotics.