Here is a small note for those who take tablets splitting them. Even I used to do it often being lazy to search for tablets of dosage that I wanted. However, now I have changed this habit of mine, since there are a range of options available for those tablets.
Many researchers warn that splitting tablets into two or more parts is potentially dangerous (since tablet parts are often unequal in size) and could lead to people taking the wrong dose. Specifically, with regard to pills that have a narrow margin between a therapeutic and a toxic dose, it is more dangerous. A study published in the Journal of Advanced Nursing has revealed that 31 percent of split tablets deviated from the recommended dose by at least 15 percent and sometimes by more than 25 percent. The study suggested that the pharmaceutical firms should produce a range of options, including smaller or bigger dose tablets.
If suppose the dosage prescribed for you is not available in the market, then I feel it is better to talk to your doctor about it once, and confirm if it is fine to split tablets to take recommended dose.
Take care, and be healthy!