Narrative:

The flight attendants initially called and told the cockpit that all four flight attendants were getting dizzy and nauseous and one reported a tightness in her chest. We found out later that it was actually only three of them. I advised them to stop the service and; if they felt it would help; to go breathe oxygen in the back galley with the curtain closed. We were at FL350 and our cabin altitude was 7;000 ft. We descended to FL310 to lower the cabin to 5;000 ft. The descent made no difference. While we were doing this we contacted dispatch and med link for assistance. The first officer; off line jump seater and myself also all briefly donned our oxygen masks as a precaution but then just kept them ready in case we started to feel any symptoms as well. None of us did at all. We asked the flight attendants to discretely ask if the deadheading crew in the back noticed any symptoms. They did not. No passengers reported any symptoms either. Med link offered for them to take either one benedryl or one ondansetron and to continue breathing oxygen. The flight attendants didn't want to take the medication. After breathing oxygen for a few minutes they felt they could finish the service and did so. I told them that they did not need to finish the service and that I was more concerned about them. I also offered to divert immediately if the flight attendants needed me to and they all denied the offer saying that it wouldn't be necessary. We landed uneventfully where we had paramedics; mechanics and inflight supervisors meet the airplane. The three flight attendants had their vitals checked and were all normal upon landing. We reported the airplane as completely normal from our perspective to maintenance and wrote up three oxygen bottles in the maintenance release. I stayed with the crew until all flight attendants were checked and then went to my next flight.

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Original NASA ASRS Text

Title: B737 Captain reported that three of the four flight attendants inexplicably became ill during the flight.

Narrative: The flight attendants initially called and told the cockpit that all four flight attendants were getting dizzy and nauseous and one reported a tightness in her chest. We found out later that it was actually only three of them. I advised them to stop the service and; if they felt it would help; to go breathe oxygen in the back galley with the curtain closed. We were at FL350 and our cabin altitude was 7;000 ft. We descended to FL310 to lower the cabin to 5;000 ft. The descent made no difference. While we were doing this we contacted Dispatch and Med Link for assistance. The First Officer; off line jump seater and myself also all briefly donned our oxygen masks as a precaution but then just kept them ready in case we started to feel any symptoms as well. None of us did at all. We asked the flight attendants to discretely ask if the deadheading crew in the back noticed any symptoms. They did not. No passengers reported any symptoms either. Med Link offered for them to take either one Benedryl or one Ondansetron and to continue breathing oxygen. The flight attendants didn't want to take the medication. After breathing oxygen for a few minutes they felt they could finish the service and did so. I told them that they did not need to finish the service and that I was more concerned about them. I also offered to divert immediately if the flight attendants needed me to and they all denied the offer saying that it wouldn't be necessary. We landed uneventfully where we had paramedics; mechanics and inflight supervisors meet the airplane. The three flight attendants had their vitals checked and were all normal upon landing. We reported the airplane as completely normal from our perspective to maintenance and wrote up three oxygen bottles in the Maintenance Release. I stayed with the crew until all flight attendants were checked and then went to my next flight.

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.