About us

Georg Boonen«We develop innovative phyto-pharmaceuticals for selected indication areas to improve patients’ health and quality of life.»

(Dr. Georg Boonen, CEO Max Zeller)



Max Zeller Söhne AG specialises in the development, production and marketing of phyto-pharmaceuticals with clinically proven efficacy, safety and tolerability. Zeller is a medium-sized Swiss company owned by the same family for five generations.

Over the past 150 years, the company has grown from a small pharmacy in Romanshorn to a manufacturer of ”state of the art“ phyto-pharmaceuticals.

Today, Zeller is a leader in the Swiss market for phyto-pharmaceuticals and one of the few companies that controls the entire value chain from seed to finished product. At the Zeller sites in Romanshorn and Uttwil (VitaPlant), there are 135 employees in diverse disciplines such as biology, agriculture, process engineering, pharmacy and medicine. Patients benefit from Zeller’s phyto-pharmaceuticals both in Switzerland and worldwide.


History Milestones


Paul Friedrich Gaupp and Max Zeller opened the first Zeller pharmacy in Romanshorn in 1864. The second pharmacy followed four years later and had a room for “secret ingredient production” since Max Zeller was already manufacturing his own products at that time. A third pharmacy followed in 1911. For this early manufacture, Max Zeller bought plants from local farmers.


Zeller Wonderbalm

The first major Zeller product was a so-called “Wonderbalm” (Zeller Balm) which became extremely popular as a herbal remedy for the treatment of stomach complaints.

Wonderbalm consisted of carefully selected and extracted medicinal plants (aromatic resins, roots, barks and blossoms). Antispasmodic, anti-inflammatory, analgesic and digestion-promoting properties have been attributed to these various plant components. Interest from abroad led to the rapid success of the Wonderbalm and soon it was sold in 14 countries. In the 1950s sales of the Wonderbalm reached several million units worldwide.



At the beginning of the 20th century, Max Zeller’s sons followed their father’s footsteps and the company became the partnership Max Zeller Söhne. The increasing success resulted in the existing pharmacies being modified and expanded. From then on, medicinal plants were no longer obtained only from Switzerland but also from Africa and India. The acquisition of the factory building in 1920 meant the beginning of the industrial manufacture of phyto-pharmaceuticals. The consequences of the Second World War left a considerable backlog and thus the operation needed to be reorganised and modernised. The first assembly line went into operation in 1949 and the company tripled the output over 10 years growing to 70 employees.


Pharma Business

The factory was supplemented in 1977 by a laboratory for both research and development (R&D) as well as quality control. Despite Zeller‘s growth, it became clear that Zeller was still too small to be able to finance the increasingly important research and development and the corresponding technology. As a result, in 1985, a cooperation with Ciba- Geigy (now Novartis) was started. There was also cooperation with universities such as ETH Zurich and the Universities of Basel and Bern. In 1990 allocation for R & D reached 15 % of total revenue.


Zeller today

To complement the existing Zeller OTC business, Zeller Medical AG was founded in 1996 to support cooperation with physicians. Together, Zeller OTC and Zeller Medical, represent the cornerstone for evidence- based phyto-therapy in Switzerland. Zeller products from the Women’s Health Portfolio were first offered abroad in the 1990s.

Today, we are a leading company in developing, manufacturing and distributing evidence-based phyto-pharmaceuticals with highest quality standards in Switzerland. Zeller products are registered as medicines and marketed worldwide in markets such as Germany, Japan, Brazil and Australia.


Zeller controls all processes from cultivation of the medicinal plants up to the production of the finished-packaged product: from seed to patient. To obtain comprehensive documentation of the products, Zeller implements pre-clinical and clinical trials, which are published in internationally recognized peer-reviewed journals.

Guaranteeing control of the entire value chain requires long-term investments in infrastructure. Zeller is committed to Switzerland as the home market and is consequently investing in the sites in Romanshorn and Uttwil.