 The main aim of this study is to investigate the benefits of switching from Efavirenz taken in combination with Kivexaor as part of the combination pill, Atripla in patients with Central Nervous System CNS side effects such as difficulty with sleeping, bad dreams etc. The study aims to investigate the effect of switching Efavirenz to Dolutegravir while continuing Truvada tenofovir plus emtricitabine, two constituents of Atripla or Kivexa. Dolutegravir will be the only new component of the combination. 