Late-summer hay fever that does not fit birch or grass? Amaranth, also called pigweed, is a field weed whose pollen flies from July into autumn, and it belongs to a plant family whose members strongly resemble each other. Our test checks IgE to amaranth pollen as part of 300 allergens and allergen components, next to its relatives goosefoot and Russian thistle.
Redroot pigweed (Amaranthus retroflexus) is a fast-growing weed from North America that has spread across Europe's farmland. It thrives in heat and loose, disturbed soil, and each plant can release large amounts of wind-borne pollen.
It belongs to the amaranth family (Amaranthaceae), which also includes goosefoot (lamb's quarters), Russian thistle, spinach and beet. The weedy members of this family have pollen proteins that look very alike, so sensitisation to one often comes with the others.
Amaranth pollen causes the usual late-summer hay fever set: sneezing, a runny or blocked nose, itchy eyes and sometimes a cough.
Its season overlaps with mugwort, ragweed and goosefoot. In many places these weeds grow side by side on the same field edges, so symptoms alone rarely tell you which one is behind them.
Pollen from amaranth, goosefoot and Russian thistle cross-reacts strongly. If your blood has IgE to one of them, it often has IgE to the others too. That does not mean you have three separate problems; it can be one sensitisation showing up three times.
Seeing all three on the same report, together with Russian thistle's Sal k 1 marker, helps a doctor read that pattern.
From a finger-prick sample, the lab measures IgE to a whole amaranth pollen extract as part of 300 allergens and allergen components. Goosefoot (whole extract and Che a 1), Russian thistle (whole extract, Sal k 1 and Sal k 5), mugwort and ragweed are on the same report.
A positive result means your blood shows IgE to amaranth pollen. That is sensitisation, not a diagnosis. Each value gets a class from Negative to Very high, to discuss with a doctor.
Page last updated
One finger-prick sample checks IgE to 300 allergens and allergen components, from birch and peanut to cat and house dust mite. Post it to the lab, and about 5 days after it arrives you get a value for every one. Our plain-English guide shows you how to read them. €399 in total, €1.33 per allergen.
In central Europe amaranth flowers from about July to September, sometimes into October in warm years. It overlaps with mugwort, ragweed and goosefoot.
Not necessarily. Pollen and seeds contain different proteins, and grain amaranth is usually a different species from the weed. Our test measures IgE to the pollen, not the grain. If you have reacted after eating amaranth, mention it to a doctor.
All three belong to the amaranth family, and their pollen proteins look very alike. IgE made against one often recognises the others. It is common to see all three positive together.
