False ragweed (Parthenium hysterophorus), also known as parthenium weed, is an invasive plant species native to the Americas but now found across many parts of India. It belongs to the Asteraceae family and is a notable allergen due to its highly potent airborne pollen. The plant typically flowers in late summer and autumn, releasing pollen that can trigger allergic rhinitis, asthma, and contact dermatitis in sensitive individuals. Inhalant allergy tests often include false ragweed due to its increasing prevalence and allergenic strength.
It can cause sneezing, runny nose, itchy or watery eyes, respiratory discomfort, and in some cases, skin rashes or eczema due to contact sensitivity.
It typically pollinates from late summer to autumn, depending on the local climate and growing conditions.
Although both belong to the Asteraceae family and share allergenic potential, they are different species. However, cross-reactivity may occur in sensitive individuals.