Ragweed is primarily associated with causing allergic rhinitis (hay fever), but interestingly, standardized ragweed pollen extracts have been developed and scientifically validated for use in allergen-specific immunotherapy (also known as allergy desensitization therapy) for patients with ragweed pollen-induced allergic rhinitis. Several randomized, double-blind, placebo-controlled clinical trials have demonstrated that sublingual ragweed immunotherapy tablets (e.g., Ambrosia artemisiifolia extract) reduce symptom severity and the need for symptomatic medication in individuals with ragweed-induced rhinitis. Regulatory bodies such as the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have approved ragweed pollen extracts for this purpose based on evidence from these trials.

The mechanism involves gradually exposing the immune system to controlled amounts of the allergen, promoting immune tolerance and reducing hypersensitivity reactions upon natural exposure to ragweed pollen. This approach is supported by several meta-analyses and clinical guidelines, which recommend allergen immunotherapy as a disease-modifying treatment for allergic rhinitis in appropriately selected patients. Therefore, while ragweed itself is not used as a remedy in the traditional sense, its standardized extracts have a well-documented, scientifically validated application in the medical management of allergic rhinitis caused by ragweed pollen.