bad reaction to laundry detergant?

recently, i’ve switch laundry detergents, and i noticed that when i wore underwear that’s been washed in it, i get SUPER itchy down there. i have since then switched back, but if i wore a pair of underwear washed in the new one, i itched for even a day after wearing it. it was horrible, all i could do was itch. since changing back, the itching has completely disappeared.

i know you guys aren’t doctors, but i’m wondering if anyone else has had something similar? i’ve never had something like this happen. i thought it could’ve been an infection but it went away as soon as i stopped wearing underwear washed in it. i believe the brand was arm and hammer.