I can prescribe any drugs listed in the BNF (this contains all drugs licensed in the UK). The mental health drugs include antidepressants and antipsychotics among others. All drugs, including paracetamol, have side effects so it is important to balance the pros and cons carefully before prescribing them. The positive effects are that they can help improve the mood or hope people stop hearing voices or help them calm down I they are too stressed. The negative effects are they can make people too sleepy if they get too much and some can put on weight.