Sputum Induction FAQ

Sputum induction is a procedure to help you cough up secretions (sputum) from your lungs more easily. 



What is sputum and why is it tested?

Sputum is the thick mucus, or phlegm, that comes from your lower airways (lungs and windpipe). Your doctor may order a sputum test to diagnose a lung or airway infection, such as pneumonia. A sputum test is also used to determine whether you have active tuberculosis.

How is a sputum sample collected?

To provide a sample, you have to cough up the sputum from deep within your lungs into a small container. If your cough is too shallow or dry, you won’t be able to provide a good sample.

What’s the purpose of sputum induction?

Sputum induction is used to create extra moisture in the airways of your lungs, which helps loosen and thin out secretions so they’re more easily coughed up. It assures a good sample for testing.

How is sputum induction performed?

You’ll inhale a sterile saline through a mouthpiece for several minutes to loosen phlegm in your lungs. A respiratory therapist will provide instructions and offer guidance. There are no risks associated with the procedure or any special instructions to follow after the procedure.

Is there anything special I should do before the procedure?

Don’t eat anything two hours before the procedure.

Is there any paperwork I need to fill out before I come in for the procedure?

Be sure to download and fill out our pre-admission and medication forms.

Where do I go for the test?

  • Mountain View campus – The pulmonary function testing lab, located in the old main hospital.
  • Los Gatos campus – The respiratory therapy department, located in the main hospital.

When will I get results?

Your doctor will contact you with the results within a few days.