A Cleveland Clinic doctor was hailed a hero for saving the life of a Philadelphia woman, who had an allergic reaction on board an American Airlines flight Saturday. Ashley Spencer, 28, was traveling to Cleveland for treatment of a serious illness but went into anaphylactic shock due to a peanut allergy.

Spencer had eaten a bag of chips before boarding her flight that reportedly triggered an allergic reaction while she was mid-air on the plane. In an interview with Cleveland ABC affiliate WEWS, Spencer said she passed out shortly after the plane took off​.

"I stopped breathing," she said. "I still had a pulse. That's when the stewardess said, 'Is there any medical professionals on the aircraft? It's an emergency.'" 

Flight attendants asked if there were any medical professionals on the flight, and Dr. Erich Kiehl stepped up to help Spencer, who was traveling to Cleveland to get treatment for eosinophilic granulomatosis with polyangiitis (EGPA), a rare autoimmune disease that causes inflammation in a person's blood vessels. 

Kiehl reportedly injected Spencer with an EpiPen four times and monitored her vitals over and over.

"When a person is going into anaphylactic shock it has to be taken seriously," Spencer said. "Having Dr. Kiehl on board was so important. He was monitoring the heart completely." 

The plane later made an emergency landing in Pittsburgh and Spencer was rushed to the hospital, where she is recovering from the reaction. 

"I am beyond thankful," she said. "I could have died up there."

Food allergy symptoms:

According to the American College of Allergy, Asthma and Immunology, more than 50 million Americans have an allergy of some kind with food allergies estimated to affect 4 to 6 percent of children and 4 percent of adults.

Eight types of food account for about 90 percent of all reactions, including eggs, peanuts, tree nuts, milk, fish, shellfish, wheat and soy.

Symptoms of an allergic reaction may involve the skin, the gastrointestinal tract, the cardiovascular system and the respiratory tract. 

1. Vomiting 

2. Stomach cramps

3. Shortness of breath

4. Wheezing

5. Repetitive cough

6. Tight, hoarse throat

7. Trouble swallowing

8. Swelling of the tongue

9. Weak pulse

10. Pale or blue coloring of skin

11. Dizziness or feeling faint

12. Anaphylaxis, a potentially life-threatening reaction