The bureau and the Department of Revenue shall monitor the price of medical cannabis sold by growers, processors and by dispensaries, including a per-dose price. If the bureau and the Department of Revenue determine that the prices are unreasonable or excessive, the bureau may implement a cap on the price of medical cannabis being sold for a period of six months. The cap may be amended during the six-month period. If the bureau and the Department of Revenue determine that the prices become unreasonable or excessive following the expiration of a six-month cap, additional caps may be imposed for periods not to exceed six months.