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What: Shares of DexCom (Nasdaq: DXCM) have gotten crushed today, down 25%, after the company reported quarterly earnings last night.

So what: The medical device company brought in revenue of $18.3 million, which resulted in a net loss of $0.20 per share. Both figures were below the consensus estimates of $19 million in sales and a net loss of $0.16 per share.

Now what: The gloomy figures triggered a number of analyst downgrades, such as SunTrust Robinson Humphrey, who downgraded the stock from "neutral" to "reduce," and Morgan Keegan, who downgraded it from "outperform" to "market perform." In contrast, Canaccord Genuity is keeping its "buy" rating while adjusting its estimates, but believes DexCom is still well positioned. Expectations aside, the company is still growing top-line revenue at an admirable pace, 56% over last year.

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Fool contributor Evan Niu holds no position in any company mentioned. Click here to see his holdings and a short bio. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.