Plus lenses are spherical lenses that correct for hyperopia known as far-sightedness, and/or presbyopia. Their diopters values are positive (e.g. +1 SPH). They are often available over-the-counter, without a prescription. Cheap drug store reading glasses are not customized to your Pupillary Distance measurement, and may be of inferior lens quality.
Plus lenses are sometimes used for myopia prevention in kids, however remember to always know what you are doing before implementing focal plane changes, especially in children.
Plus over Contacts
Plus lenses may be useful as differentials to tone down the power of contacts, but should be customized to your PD and your distance to blur, so it may be best to order them custom just like any other lens.
EM finds that this usage of plus lenses is generally safe.
Plus lenses can be, and sometimes are, sparingly used by individuals dealing with the last diopter. Plus lenses can and often do cause more problems than they solve in this application however, so ensure you have a full understanding of the appropriate usage before implementing them. The references included here should help you get started.
The EndMyopia method is not a proponent for "plus lens therapy". There are methods that advocate for this "hack" but EM strongly encourages individuals to understand that shortcuts really don't work and that all focal plane changes should be informed decisions that are approached with caution.
EndMyopia used to specify plus lenses to be used as a differential during the last diopter but has since changed their stance to use it as a last resort, gradually increasing their use from 25% to 50% of the time to test whether it is viable for increasing positive stimulus. Consider the old opinion from https://endmyopia.org/my-own-experience-with-low-myopia/
It’s a bit of a different game, the last diopter. For one, you really need the plus lens for close-up here. No two ways about it. You also want to be fully equalized, have sorted out latent astigmatism, and always remember to not lean in, to blink clear any blur.
versus the new opinion of using them as a last resort.
However, some people faced issues with double vision when misusing plus lenses.
The EndMyopia Blog: