Hello..... You can take the 2 medicines together.... There should be a gap of abt 30mins between the 2medicines....there will not be any interaction. I don't know how beneficial will Shilajeet Rasayanwati be...for Anxiety/Insomnia...as far as my knowledge goes....its more for general weakness.... Kali Phos 6x will be a good medicine for Anxiety & Insomnia....take 3tablets 3times a day....& watch for abt a month...if there is no improvement....then I suggest consult some good Homoeopath nearby....who will try to analyse the cause...understand your symptoms, nature, temperament & then give medicines...

It doesn't have side effects even if taken along with allopathic medicine. Kali phos is one of the medicine for anxiety and insomnia but not always. Usually homoeopathic physicians​treat such cases on the basis of signs and symptoms, modalities, family history, past history, desire and aversion, mental health, etc. Please consult your homoeopathic physician.