During Clark Kent's time at Smallville High, he had an encounter with a group called the Cheerleaders of Devotion. Mandy, Mara, Mary, and Rhonda were in that group and created a substance in their chemistry class to control their boyfriends which was called a "love molecule" and never would have done it without kryptonite.
Mandy was responsible for creating the "love molecule" by combing it with a sports drink and then her friends realized they could make their boyfriends do whatever they wanted. The Cheerleaders of Devotion put the love molecule into the water coolers during football practiced and the placers who consumed it was brainwashed to do be completely devoted to their girlfriends without caring about their own well being. Clark Kent was only sick because of the beverage instead of being affected by it since he was from Krypton.
To cure those who were brainwashed, Clark feigned affection to Mandy while Lois Lane stole the formula from her face and figured out how to break the potion's influence: exposing the infected to extremely high temperatures.
Information About Love Molecule
The Love Molecule was a hormone called phenylethylamine and acted as a love potion with combined with kryptonite. When consumed, a person becomes completely devoted to whoever they're interested in and doesn't trust anyone who looks at them with affection. The Cheerleaders of Devotion used this to make their football player boyfriends completely devoted to them without doubts about the plan even though the football players who be driven to homicidal tendencies when they become extremely jealous. Jason Teague, Chloe Sullivan, and Dan Cormay all had changed personalities after consuming the beverage and the only way to cure them was exposure to extreme heat. Clark Kent was only weakened by the serum that was developed.
The following is from the notebook of one of the Cheerleaders of Devotion
It is a natural chemical that is similar to an amphetamine, suspected of causing the 'high' experienced by lovers. The theory is the production of phenylethylamine in the brain can be trigger by something as simple as the meeting of eyes or the touching of hands. The heavy emotions linked to racing pulses, sweaty palms, and heavy breathing can be clinically explained as the result of an overdose. Some scientists have noted that high levels of phenylethylamine also occur in chocolate and have theorized about explanations for why people buy chocolates not lollipops on Valentine's Day.