Maintenance: See phenytoin • IV filter and NS flush following administration not required . Dilute in NS ONLY, final concentration 2-10 mg/mL divided doses. If the patient has not already received phenytoin then give:If phenytoin is already present but the patient is still not controlled, a 'top-up' loading dose may be useful.Phenytoin sodium 'top-up' dose (mg) = (20 - measured concentration (mg/L)) x 0.7 x wt (kg)Table 2 gives the approximate increase in concentration following doses of 250–750mg. Loading doses of phenytoin (Dilantin) are used to rapidly attain therapeutic drug concentrations. In patients with low serum albumin concentrations, a higher proportion of the total (measured) phenytoin concentration is unbound and caution is therefore required when interpreting the result.The equation below gives an albumin corrected, total phenytoin concentration which can be compared with the target concentration range (10 – 20mg/L). For example, if the patient weighs 70kg and has a measured concentration of 5mg/L, a single dose of 750mg will increase the concentration to around 20mg/L (5mg/L + 15mg/L).Oral administration should be used, whenever possible. If the patient has not already received phenytoin then give:If phenytoin is already present but the patient is still not controlled, a 'top-up' loading dose may be useful.Table 2 gives the approximate increase in concentration following doses of 250 to 750mg. Common Questions and Answers about Phenytoin dose adjustment calculator. In patients with low serum albumin concentrations, a higher proportion of the total (measured) phenytoin concentration is unbound and caution is therefore required when interpreting the result.The equation below gives an albumin corrected, total phenytoin concentration which can be compared with the target concentration range (10 to 20mg/L). dilantin. Table 3 below may help with dosage adjustment. Table 3 below may help with dosage adjustment. The Phenytoin (Dilantin) Correction for Albumin / Renal Failure corrects serum phenytoin level for renal failure and/or hypoalbuminemia. The first dose should be given 12–24 hours after the loading dose.Oral or nasogastric administration should be used, whenever possible. Scenario 3: After Dose Adjustment In normal healthy subjects after dose adjustment, the phenytoin level should be drawn within six to seven days with subsequent doses of phenytoin adjusted accordingly. It is the dedication of healthcare workers that will lead us through this crisis. I am going to reduce dose by 50 mg AM/ 50 mg PM every month until I have been weaned off. Phenytoin concentrations increase disproportionately with dose; toxicity may occur if the maintenance dose is increased by more than 25 to 50mg per day. Phenytoin Dosing Calculator This initial program provides some general dosage guidelines based on population averages for the Michaelis-Menten parameters (Km and Vmax). Editorial Information For example, if the patient weighs 70kg and has a measured concentration of 5mg/L, a single dose of 750mg will increase the concentration to around 20mg/L (5mg/L + 15mg/L).Phenytoin typical doses are 3–5mg/kg/day. Initial loading dose of phenytoin for status epilepticus'Top-up' loading dose of phenytoin for status epilepticusDecision making algorithm for the administration of phenytoin formulations
Calculate maintenance dose (usually 5-7 mg/kg/day). This is an unprecedented time. Administration of phenytoin via enteral feeding tubes is not recommended due to variable absorption of phenytoin. Phenytoin dose adjustment calculator. 4 mg/kg/day*83 kg = 332 mg/day ~ 300-350 mg/day. Do you have any cautions I should be aware of?. Order phenytoin 100mg IV TID . Only use intravenous administration when these options are not feasible and where cardiac monitoring is available.Phenytoin is highly protein bound but only the unbound concentration is active. PHENYTOIN (Dilantin) infusion. These loading doses may be given on initiation of therapy, or in response to a subtherapeutic drug level in patients at high risk for seizure activity. Only use intravenous administration when oral administration is not feasible and where cardiac monitoring is available.Phenytoin is highly protein bound but only the unbound concentration is active. If the phenytoin concentration is 7-12 mcg/mL, the dose may be increased by 50 mg/day. Phenytoin concentrations increase disproportionately with dose; toxicity may occur if the maintenance dose is increased by more than 25–50mg per day. In these situations of routine monitoring (unlike the emergency situation of breakthrough seizures in scenario two), it is A rough guide to making an adjustment to the daily dose that should increase a serum level without leading to supratherapeutic / toxic levels is: If the phenytoin concentration is < 7 mcg/mL, the dose may be increased by 100 mg/day. Conversion half-life to phenytoin ~15 minutes : SE: Hypotension, arrhythmias .