Yes, it's possible - though certainly not advisable or even desirable. Amphetamine sulphate is not even worth IVing, unless to satisfy a needle fetish.
Speed paste is usually heavily cut with all manner of substances and has been through so many hands that it is actively dangerous to IM as any bacteria sits in the muscle and can multiply to dangerous levels leading to nasty infections. At least with IV, the bloodstream dilutes and distributes any nasty bugs before they can get a hold.
The best way to consume speed paste is orally.