The number of drug dealers in Washington, D.C., has increased immensely of late. I'm not talking about the illegal kind or even the drug sales reps. I'm referring to the lobbyists on Capitol Hill trying to get the best deals for big pharmaceutical and biotech companies.

No matter what your political leanings, as an investor, increases in lobbying should be acceptable, as long as the companies are accomplishing what they want. Let's take a look at some recent political outcomes and update those lobbyists' report cards.

Medicare
 Amgen (NASDAQ:AMGN) doubled the amount it spends annually on lobbyists to $10.2 million last year. That lifted it from 12th place five years ago to second place on the list of the biggest spenders on lobbying by drug companies. Only the world's largest drugmaker, Pfizer (NYSE:PFE), spends more trying to influence politicians. Amgen might even pass Pfizer this year; it already spent $9.1 million in the first half.

One of the reasons for Amgen's dramatic increase in political spending is that the pricing of its anemia drugs, Epogen and Aranesp, has come under fire from Medicare. Unfortunately, the lobbyists haven't done the greatest job of putting out that fire. Earlier this month, Medicare curtailed the reimbursement for Aranesp and Johnson & Johnson's (NYSE:JNJ) Procrit by limiting their use in cancer patients. That should do some serious damage to Amgen's top line, because sales of Aranesp accounted for $4.1 billion of its $14.3 billion in revenue last year. The lobbyists will try to get the decision reversed, but I wouldn't hold my breath.

Sepracor (NASDAQ:SEPR) hasn't fared much better. Last May, Medicare announced that it would decrease the reimbursement rate for Xoponex to the same level as that of generic asthma medications. That resulted in a 9% decrease in sales of the drug last quarter on just the drawdown in inventories; revenue from Medicare sales is only going to get worse from here.

A reauthorization
The Prescription Drug User Fee Act (PDUFA) increases funding for the Food and Drug Administration through fees paid by the drug companies. The companies don't mind paying the fees because they increase the size, and more importantly the speed, of the FDA.

For drug companies, the goal of the fourth reauthorization of the PDUFA was more about minimizing restrictions than it was increasing the spirit of the original PDUFA: drug companies paying for speeding up things at the FDA. Overall, I'd say the lobbyists did an acceptable job at getting the drug companies what they needed.

No. 1 on their list was probably keeping any restrictions on direct-to-consumer (DTC) advertisement out of the bill, which was successful. All you have to do is look at the evening news to see that spending on DTC advertisements has increased substantially in recent years. And for good reason -- they result in increased drug sales.

One loss for the drug companies was actually a gain for investors. Much of the clinical trial data will be made available in a database for anyone to see. It will cost the pharmaceutical companies a little to input the data, but I think it's a relatively small price to pay for increased scrutiny.

Follow-on biologics
In this round, it's drugmakers fighting each other, with generic-drug makers such as Teva Pharmaceutical (NASDAQ:TEVA) facing biotech companies such as Amgen and Genentech (NYSE:DNA), among others. They're fighting over whether the FDA should approve generic biotech drugs -- so-called follow-on biologics. Unlike with small-molecule drugs, there's no mechanism for generic-drug makers to gain approval for follow-on biologics.

The bipartisan compromise reached by key senators in June looked pretty even for both sides. The generic-drug makers scored the right to make follow-on biologics, and the biotech companies retained 12 years of market exclusivity. Apparently, the fight had just begun, because it seems there has been no action since the agreement was reached. Of course "no action" is a win for the biotech companies because it keeps the status quo, which is essentially a monopoly on biotech drugs even after the patents run out.

Spending investors' money properly
There's plenty of ways that drug companies can influence politicians. Large companies lobby through an organization called the Pharmaceutical Research and Manufacturers of America, which includes Amgen, Pfizer, and Eli Lilly (NYSE:LLY), among others, and there's the Biotechnology Industry Organization (BIO) for the little guy. The companies can also hire lobbyists directly or contribute directly to political campaigns.

Overall, I'd say the lobbyists haven't really done the best job of getting the most for their clients. I guess things could have been worse if the lobbyists weren't on the Hill working on behalf of the drug companies, but as a drug investor, I'd like to see the lobbyists pick up the pace a little to protect the drugmakers' interests.

The key for investors is to find drug companies that are spending their money wisely. Whether the investment is in a capital project or on Capitol Hill, it has to result in a higher payout than the initial investment. Any political spending will cut into net margins now, but that's an acceptable price to pay if the companies get what they want.

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Johnson & Johnson and Eli Lilly are Income Investor selections. Pfizer is a pick of the Inside Value team.

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