PUPPP & rash

how do u guys differentiate PUPPP rashes and drug (medication) allergy rashes? i am 38 weeks now and i thought PUPPP rashes wont occur anymore and i always rub my leg with medication oil. i use the malay traditional massage oil to massage and rub my leg before putting on socks to sleep as it helps me sleep better. but then i started to develop rashes but i am unsure if it's PUPPP rashes or drug allergy rashes. it does looks like PUPPP rashes though. #advicepls