Which magnesium is best in the evening?
Bisglycinate and citrate are the better absorbed forms and sit well with digestion. Flakes in a bath are the pleasanter option if you would rather not take another capsule.
Will valerian make me drowsy the next day?
It can for some people, particularly at higher doses. The pack carries any warning about driving or operating machinery - worth reading before the first time you take it.
Can I take these with prescribed medication?
Check first. Several herbal preparations interact with prescribed medicines. Take the pack to your pharmacist and they will check it against what you are on.
How long before I notice anything?
Nutrients like magnesium are taken as an ongoing daily supplement. Herbal preparations are generally given a couple of weeks of consistent use before forming a view.