Can obsessive compulsive disorder be treated with cognitive therapy or is medication use more common?

Both are common. Many people receive relief from ocd symptoms with medications and/or therapy. Discuss this with your doctor and select a treatment plan that's best for you. Both medications and cognitive behavior therapy are common treatments (separately and in combination) for obsessive-compulsive disorder.
OCD Rx. Responds well to both cbt &/or medication treatment. Most commonly, the medication prescription of ssri's is used as a first line of treatment. Only, if medication management is not combined to therapy, the ocd symptoms may return (even worse) if/when med(s) is/r discontinued. The best is 2 combine both or 2 use cbt alone as it gives the person the resources to overcome her symptoms on her own.
Both can be used. Both can be used together to treat ocd.