How to complete a challenge prescription meds

Answer from: Vasqi
I'm working on the same problem. My current strategy includes: Moving all the way to the forward-most position, to group the enemy. Move to one side, so enemy is positioned in one direction. Pop smoke to get snipers and big dudes off the playing field.
Pop smoke again to get the rest of them up like sitting ducks. But again, there are never 10 on screen at once. Although, new men will rush on screen as you wipe out the others, so perhaps it is possible to mow 'em down as they rush on screen.

Even still, to do it all in a single burst with extended clip is unlikely. I think the key is in the gun. I'm using: defender 2 sniper silenced with extended clip. Zru 12 smg silenced with extended clip. Currently at: chapter 10(second half) Level 24 Ninja. Stuck at: Hole in one (1) Prescription meds (3) Top tier arsenal (5) Telescopic sniper (5) $557,185 179 credits.

And I only need 5 stars to get another 50 credits (Which I'm planning to use for telescopic scope for defender 2

Answer from: Nate
I'm maxed out, 64 challenges and level 30. All you do to pass scrip challenge is to buy several pills, and use several at once. It extends your "high" time. Once you have about 45 seconds or more of high time, pick off enemies one by one at a mission where they respawn.