Drugmakers often live or die by their blockbusters. Since the drugs can make up a large percentage of total revenues, changes of the blockbusters often drive the overall changes in the top line.

In the first quarter, AstraZeneca (NYSE: AZN) did a lot more living that dying. Its top selling drug, anti-psychotic Seroquel, was up 13% year over year. Cholesterol drug Crestor is right behind Seroquel in sales thanks to a 34% increase in sales and AstraZeneca's asthma medication Symbicort also had a nice showing up, up 36% year over year.

Those large gains helped the company raise revenue by 11%. And the bottom line looked even better with earnings per share up 20% after adjusting for restructuring and acquisition charges and a one-time tax gain.

After the strong quarter, AstraZeneca upped its full-year adjusted EPS guidance by $0.15 on the low end and $0.05 on the upper end. Everything will have to fall in place perfectly to reach the $6.32 per share it reached in 2009. Last year's earnings contained a large gain from selling pandemic flu vaccine, but unlike GlaxoSmithKline (NYSE: GSK) and sanofi-aventis (NYSE: SNY), AstraZeneca didn't see substantial sales carry over into the first quarter. Sales of AstraZeneca's pandemic vaccine were $39 million in the first quarter compared to $389 million last year.

AstraZeneca's near-term future hinges on the fate of its blood thinner, Brilinta, which is currently under review by U.S. and EU regulators. But gaining marketing approval may be the easiest part, as Brilinta will have to go up against heavyweight Plavix from Bristol-Myers Squibb (NYSE: BMY) and Sanofi. Brilinta beat Plavix in a head-to-head trial, but so did Eli Lilly's (NYSE: LLY) Effient, and it managed just $8.8 million in sales last quarter.

AstraZeneca may not have enough blockbusters in the pipeline to deal with its upcoming patent expirations, but while they're still free from generic competition, investors are getting to live the revenue-growth dream.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool owns shares of GlaxoSmithKline and has a disclosure policy.