Charles Harrison Blackley Charles Harrison Blackley Charles Harrison Blackley (5 April 1820 – 4 September 1900) was the discoverer of the mechanism behind allergic rhinitis caused by pollen, commonly called hay fever. The isolation of hay fever as a condition had been known since 1819 through the work of John Bostock. Blackley was the first to connect pollen to the condition, and though he held some later discredited views, his insight was an important step in the research of allergens. His most important work was a book titled the "Experimental Researches on the Causes and Nature of Catarrhus aestivus", published in 1873. Charles
Rhinitis medicamentosa Rhinitis medicamentosa Rhinitis medicamentosa (or RM) is a condition of rebound nasal congestion brought on by extended use of topical decongestants (e.g., oxymetazoline, phenylephrine, xylometazoline, and naphazoline nasal sprays) and certain oral medications (e.g., sympathomimetic amines and various 2-imidazolines) that constrict blood vessels in the lining of the nose. The characteristic presentation of RM involves nasal congestion without rhinorrhea, postnasal drip, or sneezing following several days of decongestant use. This condition typically occurs after 5–7 days of use of topical decongestants. Patients often try increasing both the dose and the frequency of nasal sprays upon the onset of RM, worsening