Can I sue the Dentist?

The short answer is that it depends. Certainly you should not have been prescribed a medication that your dentist knew or should have known was likely to cause an allergic reaction. However, you have not indicated whether you have permanent damages, and your health insurer will have a right to be repaid from any recovery what it paid for your hospitalization. IN addition, if you took the medication knowing that it was Penicillin based you could be comparatively responsible. And the dispensing pharmacy may have included a warning that you should have read before taking the medication. So you should speak to a local lawyer who can evaluate all of these facts to determine your best course of action.

Yes. However, did you read the prescription or the pill bottle? You may be partly responsible. In addition, what are your damages other than being in the hospital for a couple of days? You may not have damages significant enough to warrant the costs that go into a dental malpractice case (you need an expert witness). However, the case may have some limited value for settlement purposes. I settled a small dental malpractice cases pre-suit a few years ago where the client was in the hospital for 5 days waiting for a small clamp to pass after the dentist dropped it down his mouth during a root canal.

Sue? Yes Injury? Hopefully not much Contributed negligence? Maybe

You can sue for anything. Will you receive any money is a different question. I had a prospective client contact me recently with a similar fact pattern. I explained that dental malpractice cases must have more significant value for an attorney to handle the matter. two days in the hospital doesn't warrant a settlement or verdict that is worth an experienced malpractice attorneys time and effort.