Physostigmine

Aka: Physostigmine

1. See Also
   1. Anticholinergic Toxicity
2. Indications
   1. Incapacitating Agent exposure (e.g. BZ, Agent 15)
   2. Anticholinergic overdose (e.g. Atropine)
3. Pharmacokinetics
   1. Reversibly binds acetylcholinesterase
   2. Related to Pyridostigmine
   3. Lasts only 45-60 minutes
   4. May require frequent redosing as below
4. Routes
   1. Intramuscular
      1. Adults: 0.05 mg/kg
      2. Child: 0.02 mg/kg
   2. Intravenous
      1. Dose: 30 mcg/kg up to 2 mg
         1. Available in 2 mg/2 ml vials
         2. Dilute one 2 mg Physostigmine vial in 8 cc NS within a 10 cc syringe and infuse slowly
      2. Infuse over 5-10 min or slower than 1 mg per minute
         1. Risk of Seizure if infused too quickly
   3. Oral: 60 mcg/kg (bitter taste, dilute in juice)
5. Protocol: Example in Adults
   1. Initial: 2-3 mg IM or 2 mg slow IV (see above)
   2. Repeat: every 30-60 minutes prn depressed mental status
   3. Maintenance: 2-4 mg IV slowly every 2-4 hours prn
   4. Taper: Slowly taper over hours to 4-5 days
6. Contraindications
   1. Cardiac conduction abnormality (Obtain EKG prior to administration)
      1. Bradycardia
      2. Intraventricular conduction delay
      3. AV Nodal block
   2. Uncontrolled Asthma or Wheezing
   3. Seizure disorder