Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. You should take plenty of fluids and salads (fresh carrots, radish and carrots) in addition to psyllium husk. Also avoid prolonged use of sodium picosulfate. Regular aerobic exercise is also important. However, as you have been operated for colonic carcinoma 2 years back a colonoscopy is recommended.I would also suggest TSH and serum calcium levels. Hope I have answered your query. Let me know if I can assist you further.