one speedy in-office injection and you can walk out with more luscious lips. But that doesn’t mean things can’t go wrong. Full cheeks, smooth skin, plump lips: Some people have them naturally, while others get a little help from their dermatologists with dermal fillers. If you can’t quite tell which category a celebrity or someone you know fits into, well, that’s the point. The latest injectable treatments are easy to get (if not cheap), long lasting, and designed for subtlety. They’re also perfectly safe, provided you’ve done your homework and go to a reputable doctor.

If the price seems too good to be true, it probably is.

If you see a deal for inexpensive filler, be skeptical. Doctors typically pay between $250 and $350 per syringe of Restylane, so if patients are paying less than that, something’s off. “You have to be careful,” adding that counterfeit and diluted filler do exist. “Ask to see the box, and look for a safety seal on it.” The price of these fillers varies depending on the amount of product needed—expect a treatment to run anywhere from $650 to $2,000.

So how do you avoid a case of lip fillers gone wrong? First off, know your dermatologist, Do not trust anyone blindly just because they have a medical title.” Secondly, talk to your dermatologist before any procedure about exactly what they’ll be injecting and the risks. “Make sure the package is opened in front of you (NOT saved in the fridge for later touch-ups!),” Dermatologists agree: if you’re going for lip fillers, it’s HA all the way.