Essential information which
must be brought to the attention of care professionals in order to
provide care in a safe and appropriate way.
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reactions can be categorised in a number of ways (e.g. by severity,
by body systems affected, or by frequency).
The following categorisation is often used:
(augmented) reactions are considered to be an exaggeration of
the medicine’s normal effect when given at the usual dose.
This category includes unwanted reactions that are predictable from
the drug’s pharmacology and are usually dose- dependent (e.g.
respiratory depression with opioids and bleeding with
(bizarre) reactions are effects that are not pharmacologically
predictable and can include hypersensitivity reactions (eg
anaphylaxis with beta- lactam antibiotics).
(continuing) reactions describe those that persist for a
relatively long time (e.g. osteonecrosis of the jaw with
(delayed) reactions, which become apparent some time after the
use of a medicine (e.g. leucopenia, which can occur up to 6 weeks
after a dose of lomustine).
(end of use) reactions are associated with the withdrawal of a
medicine (e.g. insomnia, anxiety and perceptual disturbances
following withdrawal of benzodiazepines).
here to view MHRA Website.