B737-800
Physiological - Other
Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Flight Deck / Cabin / Aircraft Event Illness / Injury
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Diverted; General Maintenance Action
Aircraft
There was an odor in the aft lavatory prior to boarding. It was inspected by the First Officer and FA-2 (Flight Attendant). First officer said we can board and takeoff with odor. In-flight the odor got strong. I; (FA-2); notified captain immediately. Passengers began to complain. First officer came out of flight deck to observe smell and he could smell the odor as well. FA- 1 came to observe the smell and her eyes started burning. Captain then advised we had to divert to ZZZ. Oxygen was administered to FA-2 because she was lightheaded with burning eyes and a headache. Paramedics met the aircraft in ZZZ.
B737-800 Flight Attendant reported an odor that had been deemed acceptable to depart intensified later in flight; which resulted in a medical issue and a diversion.