BENZODIAZEPINES

1. Used as antiSZ, anxiolitics, sedatives, insomnia, EtOH WD, muscle relaxant. Enhances GABA activity.
    
2. Only  two benzos have reliable IM absorption - Midazolam (Versed) and Lorazepam (Ativan). Thus, in seizing pt without IV access Lorazepam and Midazolam are good choices. Midazolam is better  of  the two since it is short acting and doesn't mask neuro assessment for prolonged time. Most benzos are  metabolized by liver. Dialysis not applicable being very protein bound.
3. Most common S&S are sedation and generalized CNS suppression. Respiratory suppression requires ingestion of massive amount and particularly of concern if pt has small O2 reserve (e.g. COPD). CV depression with relative bradycardia and  ¯BP can be observed.
    
4. DX is the hx and Tox. Screen (if available). Flumezanile can be given to see recovery from sedated state but this is just an academical exercise and clinically can only worsen pt's status and cause pt to seize.
    
5. Treatment is supportive. If  type of benzodiazepine ingested is known, one can predict the length of symptoms and it's T1/2 and thus guide whether pt  will be admitted or DC. Flumazenil is given if coma or respiratory depression and given 0.2 mg (2ml) IV over 30 sec and repeated q 1-2 min to total  of  3 mg. Onset of action is rapid , <2min.  Pts should be monitored closely, since  the duration action of  Flumazenil is only 1/2h, while most benzodiazepines action is longer and pt may reverse back to coma.

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