Passing Out while coughing

Well, I'm really not sure which topic my question falls under.  My brother is a 36 yr old black male and he has a cold, so we thought.  His cough has been very deep but also when he coughs alot he passes out for about 10 to 15 sec..  I don't know what the problem is and he has seen his family doctor which gave him medicine and has scheduled several test for him.  Is there anything we should be concerned about and is there anything that you can help us with to know what's going on?

Thanks in Advance

[Mukesh Garg, MD]

caregiver222 is right, passing out during deep or prolonged coughing could be due to exaggrated vagal response (vasovagal syncope)

[caregiver222]

A syncopal episode after a cough is common. It is called a vasovagal syncopal episode. The vagus nerve, when stimulated, drops the heart rate. The heart rate drop a lot. The vagal nerve meanders through the body. One of the places it wanders near is affected by a cough. This causes a biological messenger to be sent to the atrial pacemaker site reducing the heartrate.  lowers the amount of blood pumped to the brain momentarily and causes light-headness or sometimes unconsciousness. That's what's going on. This is not necessarily a cause for undue concern. Many people have extremely sensitive vagal nerves. The late Jackie Kennedy had this condition. It can cause a problem while driving.  As a mater of trivia (Hey, you might getnon cash cab)  the vagus nerve is also close to the anus. When you strain on the toilet you drop the heart-rate. This is why many cardiac patients are found dead on the toilet.

[canuhelpme1]

A related discussion, passing out while coughing was started.