Is there any type of software like SpyWare Doctor that uses real time scanning?

I am currently using Spyware Doctor in which works very well but it slows my pc down to a crawl sometimes.Is there any other spyware/Adware remover out there that offers just as good of detection and removal as Spyware Doctor in real time that wont slow my pc?
I think im gonna renew my Spy Sweeper software instead.Thanks everyone.

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Spyware Doctor with Antivirus Review