What can be the reason for a strong burning sensation in the mucous membrane after five days of using DeflaGyn vaginal gel?

DeflaGyn is usually well tolerated, although some patients may experience local hypersensitivity reactions or mucosal irritation. The "burn" described by you may be a reaction to the specific composition of the preparation (containing, m.in, silicon dioxide and sodium citrate) or the result of mechanical microtrauma during application with an applicator.

If severe burning, pain or visible redness occurs, the product should be discontinued immediately. A strong reaction may indicate hypersensitivity to any of the ingredients of the gel or a concomitant intimate infection that has made the mucous membrane extremely tender and prone to irritation.

In the meantime, you can consider using soothing preparations with hyaluronic acid or gynecological probiotics to support the regeneration of the epithelium, but after washing the intimate areas with clean water.

A sudden and severe deterioration in the condition of the mucous membrane requires an examination by a gynaecologist to rule out an allergic reaction or chemical vaginitis. If you are not able to use a stationary visit, I attach a link to the online teleconsultation:
https://www.gdziepolek.pl/telekonsultacja/z-ginekologiem

The advice is held in Polish.

The availability of Defalgyn gel in pharmacies in Polish can be checked at the following address:

https://www.gdziepolek.pl/produkty/112145/deflagyn-zel-dopochwowy-zel-dopochwowy/apteki

In cities such as Warsaw, Wrocław, Katowice, Krakow, Lublin, Gdańsk, Łódź, Szczecin, Białystok, Poznań and Chorzów, products can be ordered with instant delivery even in 1 hour thanks to the Wolt Drive service - check if the service is available in your location:

https://www.gdziepolek.pl/koszyk/szybka-dostawa?src=zf