min. As opioid analgesics in general act for much longer than this, further i.v. boluses of 100 micrograms should be given at 2-min intervals until changes in respiration, pupils or consciousness indicate response; the subsequent doses may be given by i.m. injection. A continuous i.v. infusion commencing with 2.5 micrograms/kg/h may be required for days with opioids having a long t1/, (methadone). Naloxone is also used to counter excess opioid effects after surgical analgesia or childbirth.
Naltrexone (t\ 4 h: active metabolite 13 h) is similar to naloxone but longer-acting, with duration of effect 1-3 days according to dose. It can be used orally to assist in the rehabilitation of ex-opioid abusers who are fully withdrawn (otherwise it will induce an acute withdrawal syndrome). A patient who then takes an opioid fails to experience the 'kick' or euphoria, although naltrexone does not reduce craving as does the agonist methadone. This use of naltrexone requires careful selection and supervision of subjects.
A nonopioid analgesic useful for pain in opioid addicts is nefopam (Acupan), being neither an opioid nor an NSAID. Its mode of action is not fully understood but it may involve adrenergic and serotonergic mechanisms. It is effective against moderate pain. Since it lacks the disadvantages of opioids (constipation, respiratory depression) and has greater efficacy than NSAIDs, it provides an alternative. NSAIDs may be used for pain of milder degree (see Ch. 15).
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Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.