Sedation opioids causing

Opioids are sedating and cause a reduction in processing speed in clinical populations (e.g.. Digit Symbol Substitution Test) (Wood et al. 1998). However, a study in healthy subjects did not confirm these effects on digit substitution (Walker and Zacny 1998). Improvements are seen in choice reaction time after morphine administration (Hanks et al. 1995). Deficits have been reported in early-stage visual processing (O Neill et al. 1995 Hanks et al. 1995). By comparison, morphine s cognitive effects are lesser than those of lorazepam, but milder than hydromorphone (Rapp et al. 1996 Hanks et al. 1995). 

The euphoria, indifference to stimuli, and sedation usually caused by the opioid analgesics, especially when injected intravenously, tend to promote their compulsive use. In addition, the addict experiences abdominal effects that have been likened to an intense sexual orgasm. These factors constitute the primary reasons for opioid abuse liability and are strongly reinforced by the development of physical dependence. This disorder has been linked to dysregulation of brain regions mediating reward and stress (see Chapter 32). 

Constipation and sedation occur with therapeutic doses constipation should be managed with stool softeners. In overdose, opioids cause a triad of pinpoint pupils, coma, and respiratory depression. 

Opioids cause miosis (pinpoint pupils) in a dose-dependent manner. Sedation and hearing loss are also coimnon at higher doses of opioids. 

There is an increased risk of sedation and delirium with increased age. There is also an increased risk of antidopaminergic effects such as parkinsonism due to antipsychotic drugs. Many other drugs that pass the blood-brain barrier may cause adverse effects in the elderly. The response of opioids may be increased in the elderly, resulting in oversedation (Turnheim 1998). 

Methadone is an opioid analgesic that is available for oral and parenteral administration. It is used in severe pain, in palliative care and as an adjunct in the management of opioid dependence. Compared with morphine, it is less sedating and has a longer duration of action. It may lead to addiction and can still cause toxicity when used in adults with non-opioid dependency. Because of the long duration of action, in overdosage, patients need to be monitored for long periods. 

Slows intestinal motihty Dose Adul. Initial 4 mg PO, then 2 mg aftCT each loose stool, up to 16 mg/d Feds. 2—5 y, 13—20 kg 1 mg PO tid 6-8 y, 20—30 kg 2 mg PO bid 8-12 y, >30 kg 2 mg PO tid Caution [B, +] Not for acute D caused by Salmonella sp, Shigella sp, or C. difficile Contra Pseudomembranous colitis, bloody D Disp Caps, tabs, Liq SE Constipation, sedation, dizziness Interactions t Effects W/ antihistamines, CNS depressants, phenothiazines, TCAs, EtOH EMS Use caution w/ narcotics, may T risk of constipation related to opioids OD May cause constipation and CNS depression activated charcoal may be effective, naloxone (Narcan) may be effective... 

Quazepam (Doral) [C IV] [Sedative/Hypnotic/ Benzodiazepine] Uses Insomnia Action Benzodiazepine Dose 7.5-15 mg PO hs PRN i in elderly hqjatic failure Caution [X, /-] NA glaucoma Contra PRG, sleep apnea Disp Tabs SE Sedation, hangovCT, somnolence, resp depression Interactions T Effects W/ azole antifungals, cimetidine, digoxin, disulfiram, INH, levodopa, macrolides, neuroleptics, phenytoin, quinolones, SSRIs, verapamil, grapefruit juice, EtOH effects W/carbamazepine, rifampin, rifabutin, tobacco EMS Use caution w/ other benzodiazepines, antihistamines, opioids and verapamil, can T CNS depression concurrent EtOH and grapefruit juice use T CNS depression OD May cause profound CNS depression, confusion, bradycardia, hypotension, and altered reflexes flumazenil can be used as antidote activated charcoal may be effective... 

Behavioral effects of opioids include euphoria, sedation and mental clouding. Physiological effects include respiratory depression, decreased heart rate, contraction of the pupil, constipation, nausea, and vomiting. Opioids can also release histamine from body stores, causing severe itching, hypotension, sweating, and flushing. 

Overdosing causes stupor and coma. Pulmonary edema occurs, and froth can be seen coming from the nose and mouth. An antidote for an opioid overdose is naloxone (Nar-can ), which can rapidly displace the opioid from the receptor. Overuse of dextromethorphan can induce euphoria, sedation, ataxia, increased awareness, sweating, elevated blood pressure, arrhythmia, hallucinations, and coma. Some of the dextromethorphan effects resemble those of phencyclidine. 

Nalbuphine hydrochloride is structurally related to oxymorphone and naloxone. It is approximately equipotent with morphine. Nalbuphine is metabolised in the liver to inactive metabolites. The plasma terminal half-life is approximately 5 h. The onset of analgesia is within 2-3 min of intravenous administration and 15 min after intramuscular injection, and lasts 3-6 h with an adult dose of 10 mg. With equi-analgesic doses, similar degrees of respiratory depression to that of morphine occur up to a dose of approximately 0.45 mg-kg-1. With higher doses a ceiling effect occurs. Sedation, possibly mediated by K-receptor activation, occasionally occurs. The incidence of psychotomimetic side effects is lower than with pentazocine. The abuse potential is low, but is can cause withdrawal symptoms in opioid-dependent subjects. It has occasionally been used to reverse opioid-induced respiratory depression. 

Tranquilizer, sedation, antiemetic Dose Adults. N Initial max 2.5 mg IV/EM, may repeat 1.25 mg based on response Premed 2.5-10 mg IV, 30-60 min preop Peds. Premed 0.1-0.15 mg/kg/dose Caution [C, ] Contra Component sensitivity Disp Inj SE Drowsiness, i BP, occasional tach extrapyramidal Rxns, T QT interval, arrhythmias Interactions T Effects W/ CNS depressants, fentanyl, EtOH T hypotension W/ antihypertensives, nitrates EMS Monitor ECG, may T QT interval epi may cause paradoxical hypotension, do not use fentanyl may cause HTN, do not use if possible use caution w/ analgesics and opioids may T CNS depression monitor for S/Sxs of extrapyramidal Rxns which can be treated w/ Benadryl concurrent EtOH use can T CNS depression OD May cause T of nl SEs symptomatic and supportive... 

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