From Botox to Restylane, FDA-approved cosmetic injectables and fillers all share one goal: helping make patients look younger. When injected properly, they do just that, subtly and without a jot of downtime. Patients can typically resume all their normal activities immediately after a treatment, unless they like to go to R-rated movies without their parents.

That’s not to say the injections are completely risk-free. Mild redness, bruising, and swelling can crop up in the days following a treatment, and more serious complications aren’t unheard of. The biggest risk, however, is probably confusion about which injection suits you best. Despite their commonalities, the injections are all made with different formulas and fight signs of aging in different ways.

Below, we break down the properties and effects of the seven most popular ones.

Botox and Its Almost-Twin, Dysport

What they do: Relax the muscles that cause wrinkles.

How long they last: Up to four months.

The key ingredient: Botulinum toxin type A, a protein that can cause botulism if ingested. It simply blocks nerve impulses to the muscles if injected in small doses.

How they differ: They’re made by different companies, but otherwise, there’s no consensus. Some dermatologists say Dysport diffuses more around the injection site, whereas Botox stays put.

Result if it’s not done well: A face that looks slightly paralyzed, with too many expressive muscles out of commission.

The Classic Dermal Fillers: Radiesse, Perlane, Restalyne, and Juvéderm

What they do: Smooth wrinkles by filling them with solution.

How long they last: Opinions on this vary widely from source to source. Some points of consensus, though: they all last somewhere in the 6- to 18-month range, and Radiesse is one of the longer-lasting ones. But none of them last as long as up-and-comer Juvederm Voluma (below).

The key ingredient in Perlane, Restylane, and Juvéderm: Hyaluronic acid, which occurs naturally in skin but dissipates over time. It plumps wrinkled areas because it excels at retaining water, hence its nickname, “the ShamWow of acids.”

How the Perlane, Restylane, and Juvéderm differ, in two bullet points:

• Juvéderm is infused with lidocaine, an anesthetic that numbs the site of the injection within seconds. This makes the process more comfortable.
• Perlane’s particles are bigger than Restylane’s, which means Perlane needs to be injected further below the skin’s surface to look natural.

The key ingredient in Radiesse: Tiny crystals containing calcium hydroxyapatite, which prompt the tissue around the injection site to produce more collagen. This fights wrinkles in two different ways: by filling them in for the short term and rendering skin less wrinkle-prone in the long term.

Result if they're not done well: A face that looks misshapen or lumpy. These injections need to be injected artfully to look natural.

The Up-and-Coming Dermal Filler: Juvéderm Voluma

What it does: Unlike classic Juvéderm, this doesn’t fight wrinkles—instead, it adds volume to the face. It’s the only filler FDA-approved for plumping cheeks and preventing the sunken look associated with age, or sucking on lemon drops.

How long it lasts: Up to two years, the longest of all the cosmetic injections.

The key ingredient: Hyaluronic acid, the same ingredient in regular Juvéderm. It’s available with or without Juvéderm’s signature numbing agent, lidocaine.

Result if it’s not done well: A face that looks misshapen, same as with its fellow fillers.

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