What options does Humana offer for Part D coverage of formularies?

As of 2015, the three options Humana offers for Medicare Part D coverage of formularies include the Walmart Rx plan, the Preferred Rx plan and the Enhanced plan, according to Humana. Features, including premium, deductible, drug coverage list and co-pay, differ between plans.

The Humana Walmart Rx plan offers premiums under $16 a month and no deductible on Tier 1 and Tier 2 drugs, details Humana's website. A $320 deductible applies to the Preferred Rx plan. The Enhanced plan offers no deductible, a comprehensive drug list and fixed co-payments. All three Humana plans offer co-pays as low as $0 on some 90-day supplies of Tier 1 and Tier 2 drugs.