the combination was approved for medical use in the united states in 2000. a generic version was approved in the united states in 2019. a two month supply in the united kingdom costs the national health service about £35 per month as of 2019. in the united states the wholesale cost of this amount is about 89 usd. in 2016, it was the 62nd most prescribed medication in the united states, with more than 12 million prescriptions.