According to the UCLA Police Department, the incidents were reported over the weekend and a crime alert was issued Monday.
"I was literally in the elevator and I was like, 'Hey, did you guys see this alert? Like, this is crazy,'" said UCLA student Lauren Wilbur about seeing the alert.
According to police, on Thursday, the first student attended three parties at different locations on Gayley Avenue and "developed symptoms which they did not believe were from alcohol."
Police said two days later, the second student attended a party in the 600 block of Gayley and, after being handed a drink, "developed symptoms they did not believe were from alcohol/marijuana."
One of the victims had to be hospitalized.
"It makes me feel really sad and scared, like I would never want to be in that situation," said Wilbur. "I would never want that to happen to anybody else."
The students or witnesses did not provide a description of the suspect, police said.
T.A.C.O Inc. - which stands for Team Awareness Combating Overdose - is a nonprofit started by college students in an effort to combat drug overdoses among young adults, and they're sending out a strong message to students: stay aware and stay conscious.
"I mean, after all, you're a college student, the chances are you're going to go to a party, and the chances are that you might encounter a drug that is spiked with something that you don't know what's in it," said T.A.C.O Executive Director Reem Alharithi.
But some students who spoke with ABC7 said this isn't typical behavior at UCLA.
"This is something that does not regularly happen at UCLA, and should not happen on any college campus across America," said student Chima Oluo.
Students say they do get mandatory safety trainings but that it's important to look out for one another.
"That's why you always keep in contact with your friends, always make sure you know where they are," said Wilbur. "I have my roommates location so I kind of check, but its good to have a roommate like that so you know someone's watching your back."
The incidents remains under investigation.
Anyone with information about the case is urged to call the UCLA Police Department.