Narrative:

Informed flight attendants in the aft section of the aircraft were light headed and had a headache. Turned off recirc fans; ran packs on high. Descended to a lower altitude. I had the affected flight attendants in the cockpit one at a time and had them on oxygen. They felt better. Had the same issue on [a previous flight]. Same thing. This time we wrote it up; and sent a message to dispatch. (Don't know it if is the same airplane; but it could be). I suspect hypoxia. Flight attendants immediately felt better after having some O2.

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Original NASA ASRS Text

Title: B767 Captain reported that several flight attendants in the aft section of the cabin felt lightheadedness that was reduced by O2.

Narrative: Informed flight attendants in the aft section of the aircraft were light headed and had a headache. Turned off recirc fans; ran packs on high. Descended to a lower altitude. I had the affected flight attendants in the cockpit one at a time and had them on oxygen. They felt better. Had the same issue on [a previous flight]. Same thing. This time we wrote it up; and sent a message to Dispatch. (Don't know it if is the same airplane; but it could be). I suspect hypoxia. Flight attendants immediately felt better after having some O2.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.