Recent challenges in veterinary pharmacotherapy – could medicinal plants be an option?

The use of medicinal plants has a long tradition all over the world, both in human and animal health care. Recently, the challenge to overcome the global emergence of antimicrobial resistance, has initiated numerous research activities to understand the benefits (and limitations) of herbal remedies in the treatment of infectious diseases, which can be discussed along the following lines:

1. In contrast to common antibiotics, which are generally single small molecules, plants produce complex mixtures of related substances with antimicrobial activity. These mixtures of active ingredients, impair bacterial metabolism and replication at multiple sites and hence do not easily induce the expression of specific resistance genes. This has been very well documented for many essential oils, and their different chemical classes of active ingredients.

2. In a clinical situation, bacterial infections are commonly associated with the formation of bacterial biofilms. Plants express various substances that interfere with biofilm formation, inhibiting the initial phase of quorum sensing. By this activity, herbal remedies can significantly improve and maintain the efficacy of common antibiotics in the treatment of acute and chronic infections.

3. Most herbal extracts possess not only antibacterial activity, but also anti-oxidant and anti-inflammatory properties, which contribute to an uneventful recovery from infections.

In the light of these mechanisms-based evidence for their beneficial effects, traditional plant remedies should be re-considered in the treatment of infectious diseases as they contribute to resistance avoidance and improve recovery and wellbeing of animals.