Treatment of Status Epilepticus
- Available as 50 mg/mL colourless injection
- Store vials at 15 – 30°C, avoid freezing. Protect from light.
- Diluted solution stable for 4 hours at room temperature (do not refrigerate). Observe solution for particulate matter prior to administration and discard if particulate is present.
- Solutions Compatible: ONLY in NS or RL
- Y-Site Compatible: Do NOT mix with other IV medications
- Incompatible: Incompatible with KCl, dextrose containing solutions
(For approved routes of administration by nursing personnel, refer to Policy for the Administration of Intravenous Medications.)
| SC | NO |
| IM |
YES. Due to slow and erratic absorption, the IM route is NOT recommended for the emergency treatment of status epilepticus. |
| IV Direct | NO |
|
IV Intermittent Infusion |
YES cardiac monitoring (BP, HR) recommended Usual dilution: 1 – 6 mg/mL
Doses ≤ 300 mg: dilute in syringe up to 50 mL Doses 301 mg – 600 mg: dilute in 100 mL 0.9% NaCl bag Doses > 600 mg: dilute in 250 mL 0.9% NaCl bag
Infusion rate: 1 mg/kg/min to a maximum of 50 mg/min. For patients with cardiovascular disease, do not exceed 25 mg/min. Administer via large peripheral vein or centrally (preferred) using a large gauge needle or IV catheter.
Use a 0.22 micron in-line filter. Flush line with 0.9% NaCl before and after dose. |
| IV Continuous Infusion | NO |
(For neonatal dosages, refer to Neonatal IV Drug Manual.)
Status Epilepticus
- Loading Dose: 20 mg/kg/dose IV x1
- Dose Limit
- < 50 kg: 1000 mg/dose
- ≥ 50 kg: 1500 mg/dose
Anti-Epileptic
- < 3 years: 8 to 10 mg/kg/day divided q12h
- 3 to 6 years: 7.5 to 9 mg/kg/day divided q12h
- 7 to 9 years: 7 to 8 mg/kg/day divided q12h
- 10 to 16: 6 to 7 mg/kg/day divided q12h
- > 16 years: 4 to 6 mg/kg/day divided q12h
- The infusion site must be inspected every 30-60 minutes and documented when in use and if extravasation or infiltration is suspected
- Severe hypotension and cardiac arrhythmias are associated with rates of infusion above 50 mg/minute or above 25 mg/minute in patients with cardiovascular disease
- IM Phenytoin may cause pain, necrosis, abscess formation at the injection site
- IV formulation may cause soft tissue irritation and inflammation, and skin necrosis at IV site
- Avoid IV administration in small veins.
- Purple glove syndrome (i.e., discoloration with edema and pain of distal limb) may occur following peripheral IV administration of phenytoin. This syndrome may or may not be associated with drug extravasation. Symptoms may resolve spontaneously; however, skin necrosis and limb ischemia may occur; interventions such as fasciotomies, skin grafts, and amputation (rare) may be required. To decrease the risk of this syndrome, inject phenytoin slowly and directly into a large vein through a large gauge needle or IV catheter; follow with NS flushes through the same needle or IV catheter
| Drug | Category | Management | Supportive Measures |
| Phenytoin | Irritant with vesicant properties |
Treatment not usually required
Hyaluronidase: May consider for refractory cases in addition to supportive management (Stefanos 2023) |
Apply dry warm compresses |
- Oral Phenytoin is approximately 90% bioavailable. Plasma phenytoin concentrations may increase when IV phenytoin is substituted for oral phenytoin
- Continuous cardiac monitoring is recommended during administration: Monitor blood pressure, pulse every 15 minutes during infusion for up to 1 hour after infusion is complete
- Monitor for infusion site reactions
- Monitor serum phenytoin concentrations
- Slight yellow color discolouration does not indicate potency loss
- Slowing infusion rate/decreasing solution concentration can alleviate pain at injection site
- Therapeutic Drug Monitoring
- Therapeutic Serum concentration: 40 – 80 micromol/L
- Usual sampling time: Pre-Dose (0-60 minutes prior to next dose)
- When to order levels
- Post-Loading Dose: At least 60 minutes post IV load
- Maintenance (Steady State): 3 days after dosing change
Phenytoin Sodium Injection USP monograph, Omega Laboratories
Phenytoin, Lexicomp