Reddit reviews Understanding Reptile Parasites (Advanced Vivarium Systems)

Snakes not eating is nothing to panic about. It usually indicates that something is wrong, but frantic action can make it worse. A healthy snake is not hurt by a few weeks between feedings. One week is nothing.

Remember, snakes do not need to eat very often, but eating does make them immobile and unable to use their one weapon. So if a snake feels at all threatened, frightened, or just nervous about a new environment it'll wait.

There are lots of possible reasons, but for a new snake, just being comfortable in its new environment is the most likely, and the most important three things there are the 3H club: Heat, Hydration, and Hide.

But after you change something, wait three days or so before offering food.

The other thing I strongly recommend for a new snake is a fecal exam. Get some poop while still moist, add a few drops of non-chlorinated water (contact lens saline is ideal), wrap tightly, and refrigerate until you can take it in to be checked. You can just drop it off at the front desk of a vet office. (Fecal exam is usually around $20. If you have a farmer friend, they may have the microscope and supplies to do it themselves, although that leaves you needing to get a book to figure out the treatment.)

Almost all snakes from breeders or shows are full of worms. To the point that I start with a course of fenbendazole and then bother with the exam to see what's left.