What is the crowd's opinion of
LibreTexts?
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7 reviews of this app found across the web:
Sounds like basically a platform for e courses (the content, health or math info is irrelevant to the software itself), can possibly be made based on something like moodle or libretexts.
General Chemistry texts don't change much from year to year. They shuffle the problems and the page numbers so students have to buy the current edition and pay $250-$300. Five year old used texts can be had for $20 - $30 from Amazon or Powells. There are free, but perfectly good, texts available as pdfs on openstax.org or libretexts.org , too, which are every bit as good as the expensive paper ones.
Pretty much all standard general chemistry texts are alike. You can get a free pdf of a perfectly good textbook from openstax.org or libretexts.org . In print texts, there are any number available used, like Chang, Silberberg, and others.
Warning, you can't study chemistry except at the most superficial level without algebra and a smidge of calculus. Some of the concepts are fairly dense, but they are at the core of what chemistry is about. For example, kinetics and equilibrium, thermodynamics and free energy, etc.
Don't bother with a 'Dummies' book or even Larry Gonick's cartoon guide. All of those quickly get into the weeds when they start to explain the foundation concepts of chemistry.
Honestly man, our NCERT books are terrible, especially the Physics books. Math is good for practice, but if you really want to understand check out foreign curriculum textbooks or stuff like libretexts.org and courses.lumen.
I think this answer is going to vary depending on the drug itself. I think maybe you should rephrase to be a little bit more specific, as there is no real 'blanket' answer you are going to get.
For an extremely simplified example: An overdose of methamphetamine can lead to a multitude of different things mostly relating to the heart such as how the rhythm of the heart beats, blood pressure, overheating, etc. Where as something like a fentanyl overdose can lead to extreme labored breathing that can lead to a lack of oxygen within the body (hypoxia), alongside a few other things.
There are whole fields of study as to why the specific mechanisms of an overdose occur. These fields of study are extremely complex and generally require years and years to learn.
You may want to check out some books on Pharmacology, Biology, Organic/Biological Chemistry, Anatomy, Pharmacodynamics,.....and Pharmacokinetics....and I'm sure I'm missing something.
EDIT: Here is an amazing website that contains free textbooks about various STEM related fields: https://libretexts.org/
Some more great resources:
Stitz-Zeager's Open Source Precalculus Algebra and Trigonometry