It's a teratogen causing birth defects and miscarriages, so severe that "women of child bearing age taking isotretinoin are required to register for the iPLEDGE program. The iPLEDGE program requires that women taking isotretinoin undergo frequent pregnancy tests and commit to using two (2) forms of birth control in order to prevent themselves from getting pregnant."[1]

From Wikipedia[2]: "Isotretinoin is a teratogen; there is about a 20–35% risk for congenital defects in infants exposed to the drug in utero, and about 30–60% of children exposed to isotretinoin prenatally have been reported to show neurocognitive impairment".

See also pages like r/AccutaneRecovery[3] for people harmed by using it for acne, reporting systemic damage, perhaps permanent damage.

Scroll down[1] for the picture of some of the possible side effects of oral Accutane/Isotretinoin on the mother[3] and note that Wikipedia says "the most common adverse effects are dry lips (cheilitis), dry and fragile skin (xeroderma), dry eyes[8] and an increased susceptibility to sunburn" and wonder how a beauty treatment which improves skin condition has most common side effects which ruin skin condition.

This line of inquiry leads to a fun conspiracy/woo hypothesis; Grant Genereux[5]'s claims that what it does is trigger stem cells to differentiate in the epithelial layers of the skin, which makes thicker skin in the short term (wrinkle free) and worn out stem cells and thick skin in the longer term - and that many small vessels in the body have an epithelial lining of 'internal skin' and that thickens by the same mechanism leading to narrowing and closing of all kinds of internal vessels - tear ducts and sweat glands and blood vessels and inside the kidneys and liver and inner ear, etc. which cause the dry skin and dry eyes "side effects" (direct effects really) seen outside, and the organ damage/dizziness/etc. seen inside. And that it's a teratogen by getting inside cells, damaging them, damaging the DNA/protein building mechanisms causing wider systemic damage which can be long term and is not cleared up by stopping taking Accutane, this is misunderstood as retinoids "mediating hundreds of gene expressions" but is really shotgun chaotic damage and that's why there isn't a single symptom to look for and how it gets diagnosed as many different organ-specific diseases instead of retinoid toxicity damage. And/or causing cellular apoptosis with immune system response to a percieved 'attack', which is then seen as organ damage with immune system activity present, and misdiagnosed as "autoimmune" where the immune system has decided to attack an organ for no reason, which is why autoimmune disorders never have treatments or cures and why they cluster (people with one often get more) despite no good reason that should happen.

And that this whole collection of behaviours is triggered by food with Vitamin A (retinol in the tretinoin family) in it such as dairy and meat fat and Cod Liver oil, and foods with Beta Carotene (retinoids in the same family) such as orange/yellow/dark green coloured fruits and vegetables, and fortified Vitamin A in low-fat dairy and flours and other products through the USA/Europe. And it doesn't take much more than the RDA of Vitamin A to become problematic, and once it builds up in the body beyond the level the body can handle over a few decades, it's like blue touch paper waiting to be lit. Which, he suggests, is why auto-immune disorders cluster together (if you get one, you likely get more), why Eastern Canada Prince Edward Island near a Cod Liver Oil refinery was the highest incidence of Alzheimers in the world and that has been dropping since the refinery closed, and many more connection-between-retinoids-and-disease-states including claims by other people[6].

(I called it a 'fun' idea - it is at least fun along the lines of Tyler Vigen's spurious correlation noticer. https://www.tylervigen.com/spurious-correlations even if the main idea is not true).

[1] https://www.acne.org/accutane-in-pregnancy

[2] https://en.wikipedia.org/wiki/Isotretinoin

[3] https://www.acne.org/wp-content/uploads/2021/12/04-accutane-...

[4] https://www.reddit.com/r/AccutaneRecovery/comments/1c28jgg/a...

[5] https://ggenereux.blog/my-ebooks/

[6] https://nutritionrestored.com/blog-forum/topic/the-known-his... - blog post about paper observing hypervitaminosis-A bone damage in fossil skeletons, articles observing hysteria in Eskimo women, speculated to be caused by Vitamin A toxicity from Atlantic fish liver (callback to Atlantic coast cod-liver oil refinery), connection between hypervitaminosis A and calcified arteries, connection between hypervitaminosis A and scoliosis, hypervitaminosis A in small animals causes bone growth problems and symptoms of depression.