Hi, Thanks for writing in. Morphine is an opioid analgesic and can cause hallucinatory effects in sleep in some patients and you are among them. There can also be hypnagogic hallucinations occur when falling asleep or waking. The dose of morphine might have differed or its preparation and potency was higher last year when compared to your earlier time. In such cases, the patient may be put on alternatives like oxycodone for pain relief. This is also highly potent but has lesser side effect than morphine.