The decisions regarding your dosage are extremely subjective and are different for each person so a generalized opinion cannot be given. You should always try to consult your psychiatrist in person before changing your dosage. Behavioural treatment could also be useful with OCD and a clinical psychologist could be seen with regard to this. If the problem is severely crippling and unresponsive to medicine or any other treatment for over 5 years at a stretch then neuro-surgical techniques can be contemplated but this should be recommended by your psychiatrist and under the conditions mentioned.