Catch up on today's top five analyst downgrades with this list compiled by The Fly: 1. Dollar General (DG) downgraded to Neutral from Buy at Buckingham with the firm's analyst saying the environment has become more difficult since the bullish analyst day last spring. The firm's analyst said shares do not appear to fully factor in sales and margin challenges and sees risk to Street expectations. 2. MEDNAX (MD) downgraded to Neutral from Overweight at JPMorgan with analyst Gary Taylor citing valuation following the recent rally in the shares. The analyst says he can't with confidence bump up his $69 price target given the multi-year slowdown of organic growth and its high Medicaid payor exposure. 3. Loxo Oncology (LOXO) downgraded to Neutral from Buy at Citi with analyst Yigal Nochomovitz saying the stock is now fairly valued. The reflect the equity financing in January which expanded the share count and rising R&D spend, the analyst cut his price target for the shares to $45 from $49. He believes, however, that Loxo management is executing the business plan well. 4. Kimberly-Clark (KMB) downgraded to Hold on competition, valuation at Societe Generale with analyst Iain Simpson saying price competition in the U.S. has picked up as P&G is becoming more aggressive with its mid-tier Luvs and competition in Brazil and China remains "tough." The analyst expects cost cutting to drive margins and views cash returns as "robust," but said valuation has caught up with fundamentals. 5. Ionis Pharmaceuticals (IONS) downgraded to Sell from Neutral at Goldman with analyst Salveen Richter saying Ionis has a "lackluster" track record of developing successful drugs and ongoing toxicity across multiple drugs. If volanesorsen is approved for FCS, Richter expects safety/compliance issues and the launch focus on specialists will result in limited returns, similar to drug Kynamro for high cholesterol. This list is just a portion of The Fly's full analyst coverage. To see The Fly's full Street Research coverage, click here.