An epigenetic alteration is a multiplier on the expression of a gene. it can either inhibit its expression or increase its expression, in a continuum like manner, and remarkably, in a tissue/cell specific manner. A complete inhibition is akin to a gene removal, behaviourally speaking and indeed there can be many synergies between multiples altered genes expressions.
The effects of an epigenetic alteration usually last 6 month although some consequences of the alteration might in some contextes be permanent.
Of course the main drug class for this are peptides.
An example being melatonan 2, which activate melanin in a continuous like, dose dependent manner.
so you can progressively darken your skin
https://alchetron.com/cdn/melanotan-ii-d26dbedd-94fb-434a-8d...
if abused, you can become ultrablack
https://i.dailymail.co.uk/i/pix/2015/08/15/04/2B6033FA000005...
this change is permanent.
now there are much more useful peptides out there,
for example:
thymalin, the thymus hormone, is revolutionnary as it reverse thymus involution. Thymus involution is the main programmed aging factor, which leads to your death as an evolutionnary advantage. I have discussed this topic enough the last week so I won't go into details here.
just so you know thymalin rejuvenate the thymus and increase lymphocite T naive cells production by up to 680% which totally fix immunodepression in the edlerdly and e.g. fix covid since day 1 (would have avoided 15 million deaths were people litterate) or reduce all cause mortality in humans by 410% when coadministarted with epitalon,
epitalon allow your cells to bypass the hayflick limit (maximum number of divisions). It also rejuvenate the pineal gland and therefore fix age related sleep issues.
BPC-157 significantly accelerate the time it takes for a physical injury to resorb. It is also unique in it's tendon rejenerative properties, its angiogenesis superior to VEGF, neuromodulation and its effect on IBS.
cortexin/cerebrosylin are potently nootropics and neuroprotective. Rethinalamin rejuvenate the eyes which can un-blind people in some conditions, e.g. solve glaucoma and macular degeneration.
PNC-27 is one of the most interesting peptide, since it is basically the best cure against cancer e.g. https://touroscholar.touro.edu/sjlcas/vol13/iss2/7/
there is an unlimited potential for peptides, many "incurable" diseases have seen peptides specifically made for them and acts as effective cures (e.g. multiple sclerosis), however for the most part their potential is untapped, the reason being that this tech is endogenously produced in the human body, which make them unpatentable, which makes them unlucrative and since public research clinical trials are inexistant, you will never see them massively adopted, unless by accident.