Can morphine administered by injection bring on unconsciencness in patient on fentanyl patches?

by Helen
(Gobowen)

My 82 yr old mother was recently given a morphine injection to alleviate severe arthritic pain. She has been on Fentanyl patches for many years. Some 18 hours later she was in a state of unconsciousness and was only able to communicate by eye movements with great difficulty.

Fortunately on admission to A & E the doctor realised that this could have been due to her patch and gave her an injection of something (I don't know what) which took immediate effect. Within a few minutes she was trying to form words and some hours later was able to communicate normally although a little slow. She is now fully recovered. Her patch has been decreased to 25 from 50.

My main concern though is that this was a repeat incident of last November, although that time I don't know if she took morphine prior.

Should she ever be given morphine again and if so should she admitted to hospital under observation for a few days.

Accidental Opiate Overdose

Both Fentanyl and Morphine are opiates. These are very strong pain killers that can cause reduced level of consciousness, respiratory depression, low blood pressure, dizziness, constipation and coma. Combining two opiates increases the risk of this happening and morphine should always be given with care in this situation. It sounds as the she was given too much morphine in this case. It is always a fine balance and in the elderly it is much more likely to happen.

The drug I suspect she was given was Naloxone which is an opiate antagonist which temporarily reverses the effect of opiates.

She doesn’t need to be admitted to hospital to have Morphine administered. The doctor administering it should know that she is sensitive and give a low dose to start. When administering Morphine, Naloxone should always be available in case reversal of the drug is required.




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