Thanks for your question on Health Care Magic.
I can understand your concern.
Possibility of inhalation of poison ivy is very less.
But since she is having burning in lungs, possibility of post inhalation
bronchitis is more.
It is inflammatory reaction in airways due to irritation caused by inhaled substance.
It is usually self limiting and heals by its own.
She needs to take fresh air,fluids orally etc.
But if burning sensation worsens or she develops
cough or breathlessness then better to
consult pulmonologist and start inhaled bronchodilators and inhaled corticosteroid (ICS).
At present, no need to worry much. She will mostly improve by its own.
Hope I have solved your query.
Wishing good health to your friend. Thanks.