Thesit

Thesit is a German pharmacy brand of skin products made and marketed by gepepharm GmbH, a pharmaceutical company based in Hennef, Germany [3]. The name covers two quite different products. Thesit Gel is a fragrance-free cooling gel for irritated skin, presented mainly as first aid for insect bites and sunburn. Thesit Substanz zur Rezeptur is a raw ingredient supplied to pharmacies, which use it to mix their own itch- and pain-relieving preparations.

What links the two is a single substance: lauromacrogol 400, also known under the cosmetic ingredient name laureth-9. The brand sits on the border between skin care and medicine, and its maker describes it both ways. When the Thesit name was first used, and how it came to gepepharm, has not been publicly documented. The brand remains active, with both products listed in its maker's current range.

Thesit belongs to gepepharm GmbH, which lists both Thesit products in its alphabetical overview of preparations [3]. The company was founded in 1987 by Dr. Karl-Georg Mothes, who also founded biomo pharma GmbH [2]. The company's legal notice names Dr. Karl-Georg Mothes, Diane Mothes-Grossmann and Patrick Mothes as its managing representatives [6].

gepepharm describes itself as a skin-health specialist and uses the slogan "Für ein gutes Hautgefühl" ("for a good skin feeling"). According to the company, its portfolio spans cosmetics, dermatological medicines and specialised antiparasitic treatments. Within that range Thesit sits alongside the acne-care line Aknederm, which the company presents as its key brand, the crotamiton-based Crotamitex gel, lotion and ointment, and gepescap, a permethrin cream. Independent online pharmacy listings likewise name gepepharm in Hennef as the manufacturer of Thesit Gel [7].

Thesit has no standalone website or social media presence of its own. Its product information appears only on the maker's corporate site, in the form of downloadable leaflets and a technical brochure for pharmacists.

gepepharm's stated aim is to develop products that work well and are also especially well tolerated by the skin. Thesit fits that pitch in two ways. For consumers, it is a gentle, everyday remedy for skin that has been bitten, stung or burned by the sun. For pharmacists, it is a working ingredient for prescriptions mixed on site, a practice known in German as Rezeptur.

The consumer leaflet's headline calls Thesit Gel "die effektive Soforthilfe bei Insektenstichen und Sonnenbrand", or quick relief for insect bites and sunburn. The leaflet suggests keeping a tube at home so it is always to hand, and packing it for summer holidays.

The brand's classification is not entirely consistent. The leaflet describes Thesit Gel as a cosmetic skin gel for the cooling care of irritated skin [4]. The maker's product overview, however, presents its range as medicinal products and lists laureth-9 as the gel's active ingredient [3]. Online pharmacy listings file the gel under body care and cosmetics [7]. The raw substance, by contrast, is described plainly as a surface anaesthetic [5].

### Thesit Gel

Thesit Gel is the brand's consumer product. The maker recommends applying a thin layer to irritated areas once or several times a day, and washing the hands afterwards. Retail listings show it in a 50 g pack.

According to gepepharm, the gel feels cool as soon as it is applied, spreads easily, absorbs quickly and is not greasy. The company says it contains soothing and moisturising components that help prevent the dryness and peeling that often follow sunburn. It also says the gel eases itching and burning, and that the heat and touch sensitivity of sunburned skin subside noticeably shortly after application. None of these statements is presented as the result of a clinical study.

Because the gel is entirely free of fragrance and colourants, the maker presents it as suitable for people with sensitive skin [4].

### Thesit Substanz zur Rezeptur

The second product is aimed at pharmacists rather than shoppers. Thesit Substanz zur Rezeptur is lauromacrogol 400 to the European Pharmacopoeia standard, which gepepharm describes as a surface anaesthetic for relieving pain and itching on the skin [5]. Pharmacies use it to compound individual prescriptions.

The company's brochure lists a broad range of uses. These include atopic eczema and other itchy skin conditions, chickenpox, leg ulcers, sunburn and insect bites. A 5 % solution in water is described for easing pain in wounds, burns and chemical burns, and the brochure states that, based on experience to date, it does not interfere with wound healing [5]. It also mentions use on mucous membranes, for example for mouth ulcers, inflamed gums, haemorrhoids and tonsillitis.

The brochure doubles as a recipe book. It gives worked formulas in which Thesit is typically used at 5 %, including haemorrhoid creams combining it with allantoin or with bismuth gallate in a standard base cream, and ointments for itching and leg ulcers.

Chemically, the brochure describes Thesit as a nitrogen-free, non-ionic compound built from a fat-loving dodecyl chain and a water-loving polyethylene oxide chain. This gives it detergent-like, surface-active properties, and the maker warns that it does not mix well with greasy, water-in-oil creams. It also advises keeping Thesit preparations away from lacquers and some plastics, such as the lacquered lining of aluminium tubes or spectacles, while standard polyethylene and polypropylene pharmacy jars are suitable. The substance should be stored below 25 °C. The brochure in circulation carries a revision date of December 2019.

Thesit is active. Both products appear in gepepharm's current list of preparations, and the maker republished the Thesit Gel leaflet in June 2026 [4]. The brand is sold mainly through pharmacies, and all of its product literature is published in German. No awards, press coverage or third-party certifications are documented for the brand.