Morphine deadens pain by acting at nerve synapses, but it also activates glial cells, possibly worsening the drug's side effects, such as drowsiness, tolerance, worsening of pain, and addiction.

吗啡通过作用于神经突触来缓解疼痛，但它同时也兴奋了胶质细胞，可能也加剧了该药的副作用，如嗜睡，耐受，疼痛加剧和成瘾。

youdao

This includes practicing without a doctor's supervision and prescribing narcotics such as morphine for pain.

VOA: standard.2010.05.14

The medications typically in short supply are generally low cost drugs such as morphine sulfate, zofran, compazine, reglan, ativan and valium.. The shortages often involve injectable drugs which are more technically difficult to manufacture than oral medications.

FORBES: Drug Shortages Compromise Emergency Medical Care