Definition of jack up phrasal verb from the Oxford Advanced Learner's Dictionary

Phrasal Verbs
(informal) to inject an illegal drug directly into your blood Drug users were jacking up in the stairwells. See related entries: Addiction
  1. 1to lift something, especially a vehicle, off the ground using a jack Thieves jacked up the car and stole the wheels. See related entries: Motoring problems and accidents
  2. 2(informal) to increase something, especially prices, by a large amount
See the Oxford Advanced American Dictionary entry: jack up