“First of all, “scratching to stop itching” is objective. Rubbing causes receptors to receive nociceptive signals and transmit them to the nervous system, activating intermediate neurons that inhibit the transmission of itch-related signals, thus “scratching to stop itching”. However, eye itch can be caused by different reasons and rubbing the eye without knowing the cause can be counterproductive.
If a foreign body has entered the eye, rubbing the eye may aggravate the abrasion of the foreign body on the eye and in severe cases damage the cornea and affect vision.
If rubbing is done for chronic or persistent itchy eyes, it can “get itchier” because excessive rubbing increases the transmission of itch-promoting information.
Rubbing the eye in the presence of an eye infection can cause the finger to carry pathogenic bacteria that can infect the other eye or a close family member.
In cases of poor hand hygiene, new bacteria or viruses are likely to be introduced, increasing the chances of ocular surface infection.
Therefore, in cases where the cause is not known, it is advisable not to rub the eye with the hand and to seek prompt medical attention if necessary.”