Goal Total Phenytoin Level: 10 - 20 mcg/ml (assuming normal albumin) Goal Free Phenytoin Level: 1 - 2 mcg/ml (for both normal and abnormal albumin) Now if a patient does NOT have normal albumin levels and/or has drug interactions that can affect protein binding of phenytoin, then your goal total levels will change. Only use intravenous administration when these options are not … A small change in dose can result in a massive change in plasma concentration if the saturation point is unknowingly exceeded. However if seizures are controlled at 9 mcg/mL or side effects are present at 12 mcg/mL, a patient specific therapeutic range should be considered.Phenytoin is highly protein bound. Editorial Information Critical Care and Hospital Pharmacy Resources for Hospital Pharmacists, PGY-1 Pharmacy Residents, PharmD students, and PreceptorsControl of generalized tonic-clonic and complex partial (psychomotor, temporal lobe) seizuresPrevention and treatment of seizures occurring during or following neurosurgeryPrevention of early (within 1 week) post-traumatic seizures following traumatic brain injuryTo determine if a patient has a therapeutic phenytoin level, I look at 4 things in the following order:As with all drugs, it is important to treat the patient and not the number. I know you had mentioned it’s important to treat the patient and not the number, but I’m thinking if you check the level the next day, you may be able to prevent another seizure from happening if the level is subtherapeutic. Phenytoin can be given intravenously or orally. Thank you!1. Unbound phenytoin concentrations may be more useful. If given orally, this dose should be divided into three doses (e.g. Post it in the comment section below!Hi Joe – Great podcast! In another popular pharmacist-led website they state IBW is to be used but cannot give an explanation as to why. 1000 mg given as 400 mg initially, 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). The Phenytoin (Dilantin) Correction for Albumin / Renal Failure corrects serum phenytoin level for renal failure and/or hypoalbuminemia. If the phenytoin concentration is 7-12 ug/mL, the dose may be increased by 50 mg/day. Would it be correct to reduce the Dilantin level to 300mg a day? It is the dedication of healthcare workers that will lead us through this crisis. Patient weighs 130 lbs and is 72 year female old showing symptoms of dizziness, headache and slight ataxia. actual?) The first dose should be given 12–24 hours after the loading dose. The loading dose is generally 10–20 mg/kg10. Since the ratio is 10:1 between total and free phenytoin levels, just divide the cut-offs by 10 and adjust accordingly.Thanks for such a great podcast! How often should blood test be given during administration of the drug to ascertain safe levels?also should the patient be given a medalert wrist band to notify medical peronel that she is taking it?If the phenytoin level is supratherapeutic (level adjusted for albumin of 3 and hemodialysis patient) is it best to hold a few doses or lower maintenance dose ?If I had a patient like that I would consider how high the levels were and whether the patient was having side effects before deciding whether to hold a few doses or to lower the maintenance dose.How would you recommend adjusting supratherapeutic phenytoin levels?I either hold a few doses or lower the maintenance dose, depending on what is going on with the patient (how high is the level, are they having side effects, etc…).With a patient with a free level of 2.3 and level of 19.1 on Dilantin 200 mg in am and at hs along with Depakote ER 250mg in am and HS, how would you approach the elevated free level? Phenytoin concentrations increase disproportionately with dose; toxicity may occur if the maintenance dose is increased by more than 25 to 50mg per day. Thank you for everything you do. The loading dose = (goal total phenytoin level – current total phenytoin level) x weight in kilogramsCardiac toxicity may occur with phenytoin administration, even at normal infusion rates. Thank you.If I had a patient like that I would look to reduce the phenytoin dose exactly as you described.I was wondering if you could shed light on what weight is recommended to be used when dosing phenytoin? Just curious what weight other hospitals or pharmacists are utilizing. Even the 8% increase in bioavailability between the phenytoin base (oral suspension and chewable tablets) compared to phenytoin sodium (oral capsules and IV formulation) could be enough to surpass the saturation point and cause toxicity.Adjustments to the maintenance dose of phenytoin should be made in small increments. For most patients the therapeutic range of phenytoin is 10-20 mcg/mL. 2) How fast do you infuse your loading dose? (IBW? Table 3 below may help with dosage adjustment.