Skin-Quality Injectables: Which Type Suits You?

A practical comparison of the main skin-quality injectables: what each one does, who it suits, how many sessions it needs, when results appear, side effects, and where the evidence is still thin.

Aesthetics · 5 min read · August 22, 2026

Written and medically reviewed by Dr. Yousef Abo Zarad · German board-certified dermatologist · Last reviewed: September 2026

The short answer

These injectables do not fill deep wrinkles or lift the face. They improve the skin itself: hydration, smoothness, fine lines and, to a lesser degree, elasticity. The clearest evidence exists for hyaluronic-acid products such as Profhilo and skinboosters; polynucleotide studies are still small and of limited quality; and diluted calcium hydroxylapatite (CaHA) is used mainly for thin skin and mild laxity of the neck and chest.

Dry, dull skin with fine lines: skinboosters or Profhilo.
Thin, crepey skin around the eyes: polynucleotides may be used, with the caveat that the evidence is limited.
Thin skin and mild laxity of the neck or upper chest: diluted calcium hydroxylapatite (CaHA).
Deep lines, volume loss or clear sagging: these injectables are not enough on their own; filler or another treatment is chosen after assessment.

A product name is not a diagnosis. Dr. Yousef starts by defining what needs to improve, then chooses the category that fits.

What these injectables improve, and what they do not

Before any injection, Dr. Yousef therefore assesses skin thickness, elasticity, the type of lines, volume, pigmentation and vessels. Each needs a different tool, and blending them all under the word "glow" explains many disappointing results.

Usually improve: hydration, surface texture, radiance, fine lines and, to a lesser degree, elasticity.
Do not treat dynamic lines such as frown lines or smile lines around the eyes; those respond to botulinum toxin.
Do not restore lost volume in the cheeks or under the eyes; that is the role of filler.
Do not treat melasma, pigmentation, visible blood vessels or advanced laxity; each needs a different treatment.

Skinboosters

Skinboosters are hyaluronic-acid products injected into the dermis in small amounts spread across the face. The aim is better hydration, smoothness and fine lines, not added volume or a change in facial shape.

They are usually given as two or three initial sessions followed by maintenance. In a study comparing two and three initial sessions, most participants in both groups improved, and self-rated improvement held up better over the first months with three sessions.

Results are not permanent: the body gradually breaks down and absorbs hyaluronic acid, so maintenance sessions are needed to keep the effect.

Profhilo

Profhilo is a highly concentrated, non-cross-linked hyaluronic acid (not chemically bonded like conventional filler) that combines molecules of different weights. It spreads within the skin to improve hydration and radiance rather than build volume.

The standard protocol is two sessions about one month apart, with five injection points on each side of the face per session, followed by maintenance as needed.

Common after-effects are redness, swelling or mild pain at the injection points, usually settling within three days. Post-marketing data from more than a million patients recorded a very low rate of adverse events.

Polynucleotides

Polynucleotides are purified DNA fragments derived from salmon or trout, marketed for skin quality and regeneration and often used around the eyes and for fine lines.

Studies typically use three to four sessions two to four weeks apart. The available studies show promising results for lines and skin texture, but the evidence is of low to moderate quality and stronger studies are needed.

Dr. Yousef therefore presents them as a possible option in selected cases, not as a strongly proven treatment. If you have a fish allergy, tell your doctor before treatment because of the source material.

Diluted calcium hydroxylapatite (CaHA)

Calcium hydroxylapatite is primarily a filler, but when heavily diluted its filling effect drops and its purpose becomes stimulating the skin to produce collagen and elastin.

It is used on the face, neck and upper chest for thin skin and mild laxity. In a neck study, horizontal neck lines and laxity improved in most participants after two sessions, and dermal thickness increased on ultrasound.

An important safety difference: hyaluronic-acid filler can be dissolved with the enzyme hyaluronidase if a problem occurs, but CaHA is not dissolved by it. Area, depth and amount therefore need even more care.

Can they be combined?

Sometimes, but a combination needs a clear reason and order: for example filler to restore lost volume, then skin-quality injections, or pigment treatment alongside them. Stacking several products in one session because each is "good" is not a treatment plan, and it makes it hard to tell what helped and what caused a problem.

What to expect afterwards, and when to call your doctor

The most serious complication of any cosmetic injection is product entering a blood vessel, which can cause skin damage, stroke or loss of vision. It is rare, but it is why injections belong with a trained doctor using a reliable product.

Common and temporary: redness, swelling, pain or itching at injection sites, and sometimes bruising.
These usually settle within a few days.
Contact your doctor immediately for severe or worsening pain, skin turning white, blue or purple, or any change in vision.

Tell your doctor before treatment if you have

Pregnancy or breastfeeding.
An active infection or inflammation at the injection site, such as inflamed acne or cold sores.
A previous allergy to any injectable or to fish.
Medicines that increase bleeding or bruising.
Autoimmune disease, or previous filler or procedures in the same area.

Common questions

Do they replace filler? No. Filler restores volume; these injectables improve skin quality. One face may need both for different reasons.
Are results permanent? No. Hyaluronic acid breaks down over time, so results need maintenance.
Profhilo or skinboosters? Both are hyaluronic acid for skin quality; they differ in formulation, how they spread and the protocol. The choice depends on the area, the skin and the goal.
When will I see results? Improvement is gradual and is usually judged after the initial sessions are complete, not right after the first one.

Key numbers

Profhilo: 32 mg high- and 32 mg low-molecular-weight hyaluronic acid in 2 mL; two sessions 30 days apart; five points on each side of the face.
Profhilo post-marketing data: more than one million patients between 2018 and 2023, with a reported adverse-event rate of 0.034%.
Skinbooster: in one study, the result at 3 months was similar after two initial sessions and after three.
Polynucleotides: studies have usually used 3–4 sessions 2–4 weeks apart.
Diluted CaHA for the neck: two sessions 45 days apart in one study, with improved neck lines and laxity at about 4 months.