[Rozu]

I came across Macrolane breast injections and was going to ask about it here, but I found that it's no longer available. Does anyone know what happened to it exactly?

[Lotus]

Look in this study, there was rare side effects to some participants. 

Complications and management of breast enhancement using hyaluronic acid
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4173863/

On average, 30 mL to 40 mL of Macrolane was injected into each breast. Of 274 women who returned to the clinic during 2007, <10% experienced local adverse events (eg, gel dislocation, Macrolane nodules and rare cases of infection). There were no serious systemic events and treatment was well tolerated. To prevent local complications, such as infection, an aseptic injection technique was required and early treatment of adverse events is recommended. While only small volumes of Macrolane were injected, it is comparatively easy and safe to perform breast enhancement of up to one cup size to correct asymmetry between breasts and to create fullness in the upper portion of the breast.

Breast enhancement using Macrolane™: A report of complications in three patients and a review of this new product
https://www.sciencedirect.com/science/ar...1510001087

Hope this helps.