Calcium hydroxylapatite (Radiesse)

Also known as: Radiesse, CaHA, calcium hydroxyapatite

Calcium hydroxylapatite (CaHA) is a filler made of microscopic calcium spheres, the same mineral family as bone and teeth, suspended in a smooth gel. It gives immediate lift like an HA filler and also stimulates collagen as the gel carrier absorbs, with results typically lasting 12 to 18 months. FDA approved since 2006 for facial folds and HIV lipoatrophy and since 2015 for the backs of the hands, it has strong trial support for those uses. The popular newer practice of diluting it heavily and spreading it thin as a skin tightener has run ahead of the controlled evidence.

How it works

CaHA microspheres (25 to 45 microns) sit in a carboxymethylcellulose gel. On injection, the gel provides immediate volume and the spheres act as a scaffold; over months the gel absorbs and fibroblasts deposit new collagen around the spheres, which themselves slowly break down into calcium and phosphate. The result is partly instant fill, partly biological collagen response.

What the evidence says, claim by claim

These are the results measured in studies, not the results shown in ads. Where the research is weak, the grade says so.

For wrinkles and fine lines

Strong evidence

A multi-site evaluation in 609 patients supported CaHA as effective and well tolerated for facial soft-tissue augmentation including nasolabial folds, the basis of its 2006 FDA approval for moderate to severe facial wrinkles and folds. A 2024 systematic review of facial use confirms a consistent efficacy and safety record across on-label indications, with correction typically lasting 12 to 18 months, longer than most HA fillers.

Multiple randomized controlled trials or a meta-analysis support this use. The effect is real and repeatable.

Evaluation of a calcium hydroxylapatite-based implant (Radiesse) for facial soft-tissue augmentation (Plastic and Reconstructive Surgery, 2006; cohort)
A systematic review of Radiesse/calcium hydroxylapatite and carboxymethylcellulose: evidence and recommendations for treatment of the face (International Journal of Dermatology, 2024; systematic-review)

For volume loss

Strong evidence

For volume loss on the backs of the hands, a 12-month multicenter randomized blinded trial in 114 subjects found 75 percent achieved at least a 1-point improvement on the validated Merz Hand Grading Scale at 3 months, generally maintained through 12 months. CaHA is the only filler FDA approved for dorsal hand augmentation. On the face, its high lift capacity makes it a standard choice for cheeks and jawline contouring.

Multiple randomized controlled trials or a meta-analysis support this use. The effect is real and repeatable.

Calcium Hydroxylapatite Dermal Filler for Treatment of Dorsal Hand Volume Loss: Results From a 12-Month, Multicenter, Randomized, Blinded Trial (Dermatologic Surgery, 2018; RCT)

For skin laxity

Limited evidence

Diluted and hyperdiluted CaHA is widely injected off-label as a biostimulator to firm crepey skin on the face, neck, and body. The 2024 systematic reviews covering face and body use state plainly that despite wide clinical adoption and a good safety record, the diluted and hyperdiluted protocols are not yet supported by randomized controlled trials; evidence is mostly case series and consensus opinion.

Only small, short, or lower-quality studies exist. Treat marketing claims about this use with caution.

A systematic review of Radiesse/calcium hydroxylapatite and carboxymethylcellulose: evidence and recommendations for treatment of the face (International Journal of Dermatology, 2024; systematic-review)
A systematic review of Radiesse (calcium hydroxylapatite): evidence and recommendations for the body (International Journal of Dermatology, 2024; systematic-review)

Risks and what can go wrong

Common effects are swelling, bruising, redness, and temporary lumpiness, especially on the hands. Nodules can occur, particularly with poor placement or use in mobile areas like lips, where CaHA is generally avoided. Like all fillers it carries a rare vascular occlusion risk, and unlike HA it cannot be dissolved with hyaluronidase, so an experienced injector matters even more. The product is radiopaque and can appear on X-rays and CT scans, worth telling your radiologist. Avoid with active infection at the site and known hypersensitivity to components.

The practical details

Typical US pricing is 700 to 1,000 dollars per syringe. Facial correction lasts about 12 to 18 months; hand results were maintained through 12 months in the registration trial. Touch-ups commonly happen yearly. FDA approved for moderate to severe facial wrinkles and folds, HIV facial lipoatrophy, dorsal hand volume loss, and (as Radiesse Plus with lidocaine) the same facial uses; hyperdiluted skin-quality protocols on neck, chest, arms, and buttocks are off-label.