E-drug: Re: Omnopon in Pregnancy (1)
----------------------------------------------------------
Omnopon is usually the trade name for a combination of opium alkaloids
generically named papaveretum. In the UK, papaveretum formally contained
the hydrochlorides of morphine (80-84% anhydrous morphine), codeine
(6.6-7.4% anhydrous codeine), papaverine (8.3 to 9.2% papaverine
hydrochloride) and noscapine. However because of concern over the potential
genotoxicity of noscapine (ref available) UK preparations no longer contain
noscapine and the BP 1993 definition of papaveritum was changed so if the
formulation is based on the BP 1993 or later it will not contain the
noscapine. Therefore effects are basically due to morphine, papaverine and
codeine.
Morphine was widely used in the USA in labor until the 1940's when it was
largely replaced by meperidine (pethidine). Clinical impressions that
pethidine caused less respiratory depression in the newborn were apparently
confirmed. Other clinicians reported no difference between narcotics in the
degree of neonatal respiratory depression when equianalgesic doses were
used. The use of codeine during labour produces neonatal respiratory
depression to the same
degree as other narcotic analgesics. Little data could be found quickly for
papaverine though reports of opium itself used during labor gave similar
data to morphine & codeine (refs from Martindale (1982-98), Reprotox and
Drugs in pregnancy & lactation by Briggs) No reports specifically stating
"pneumonopathy (pneumopathy)" were found.
Though I am willing to do a full search of all our data bases if you would
like me to do one. Copies of references are also available and I can Fax
them to you if you require (and send me your Fax Number)
Janet McNeece Drug Information Pharmacist
Royal Adelaide Hospital
Janet McNeece
Senior Pharmacist, Drug Information centre,
Royal Adelaide Hospital
South Australia, SA5063
jmcneece@gp.rah.sa.gov.au
[Note from moderator: I think the general view now is that pethidine has
gained a place which it does not deserve. Claims of less side effects than
morphine have, as far as I remember been disputed lately. KM]
--
Send mail for the `E-Drug' conference to `e-drug@usa.healthnet.org'.
Mail administrative requests to `majordomo@usa.healthnet.org'.
For additional assistance, send mail to: `owner-e-drug@usa.healthnet.org'.