Climate change has pushed pine pollen dispersal forward by up to 19 days; South Korea's allergic rhinitis patient count nears 7.4 million; Zyrtec's pharmacy sales ranking jumps 23 spots

Zyrtec, an allergy treatment. [Provided by Geo-Young]
Zyrtec, an allergy treatment. [Provided by Geo-Young]

Rising temperatures driven by climate change have pushed South Korea's spring pollen season significantly earlier than usual, triggering an unprecedented surge in demand for allergy treatments.

Zyrtec, the country's best-selling antihistamine, saw pharmacy sales jump nearly 70% within a month, vaulting the drug into the top tier of over-the-counter rankings.

Geo-Young, South Korea's largest healthcare platform, said Sunday that pharmacy sales of Zyrtec (10-tablet packs) rose 69% in April compared with the previous month.

Data from CareInsight, a pharmaceutical research platform, covering 459 pharmacies nationwide showed Zyrtec recorded 6,539 sales transactions in April, up sharply from 3,877 in March.

The surge propelled Zyrtec's overall OTC ranking from 37th to 14th — a jump of 23 spots. The drug had already climbed 18 places in March on a 28.8% month-on-month sales increase, meaning it posted two consecutive months of exceptional growth.

The near-shortage sales trend is directly tied to the increasingly early onset of pollen dispersal each year. An analysis by the Korea Forest Service's National Arboretum found that, due to temperature increases caused by climate change, the start of pine pollen dispersal across the country has moved earlier by an average of about 0.91 days per year over the 15 years since 2010.

By region, the spring allergy season has shifted roughly five to eight days earlier across most of the country — from May 15 to May 10 in the Greater Seoul area, from May 18 to May 11 in Gangwon Province, and from May 15 to May 7 in the Chungcheong region.

The most dramatic shift occurred in the Gyeongsang region, where the dispersal start date moved from May 22 all the way to May 3 — a 19-day advance, the largest recorded. Pine pollen, which is non-toxic but triggers sneezing, runny nose and itching, has been blanketing the country from early spring, prompting patients to visit pharmacies earlier than in previous years.

A sharp rise in the number of allergic rhinitis patients is also fueling market expansion. According to Health Insurance Review and Assessment Service data, the number of allergic rhinitis patients in South Korea reached approximately 7.4 million in 2024, a jump of more than 50% from roughly 4.91 million in 2021, cementing the condition as one of the most common chronic ailments of modern life.

Against this backdrop, Zyrtec's dominance in the domestic antihistamine market — where it holds a roughly 60% share by sales value and has ranked No. 1 for 28 consecutive years — appears to be strengthening further. Geo-Young has been running a "total marketing" strategy covering retail, advertising and marketing for Zyrtec under a partnership with UCB Korea since 2023.

As a result, Geo-Young's Zyrtec supply volumes have risen each year — 2.6 million units in 2023, 2.63 million in 2024, and 2.78 million in 2025 — surpassing a cumulative three-year total of 8 million units, with a compound annual growth rate of 8.1%.

"As market volatility grows with the allergy season starting earlier due to climate change and other factors, the ability to supply necessary medicines to the right place at the right time without interruption has become more important than ever," Geo-Young Chairwoman Cho Sun-hye said. "We will do our utmost to improve patients' quality of life, drawing on Geo-Young's differentiated integrated marketing capabilities and cold-chain logistics expertise."


silverpaper@heraldcorp.com