Sheila is a 26-year-old with history of head injury and tonic clonic seizures. She
is seen today with complaints of “funny” eye movements, feeling uncoordinated,
blurred vision, and feeling lethargic. Her current medications include Ritalin 10
mg po BID, Dilantin 300 mg po BID, Paxil 20 mg po daily, Lasix 20 po daily Lab
Values from today Dilantin level of 11 Albumin 2 WBC 9.9 Plt 177 Na 141 K 4.2
Hg 13.2. What do you think is causing the patient’s symptoms? What lab values
and calculated corrected medication level support your diagnosis? What is your
treatment plan for this patient?
Answer the questions below using clinical
practice guideline where applicable. Explain the problem and explain how you would
address the problem. If prescribing a new drug, write out a complete medication order
just as you would if you were completing a prescription.
Assessment and Treatment Plan for Sheila with Suspected Dilantin Toxicity
Clinical Presentation and Diagnosis
Sheila, a 26-year-old with a history of head injury and tonic-clonic seizures, presents with symptoms of "funny" eye movements, feeling uncoordinated, blurred vision, and lethargy. Given her medical history and current medications, the constellation of symptoms is suggestive of Dilantin (phenytoin) toxicity. The symptoms align with common manifestations of Dilantin toxicity, including neurological deficits and visual disturbances.
Laboratory Values and Corrected Medication Level
- Dilantin Level: The current Dilantin level of 11 mcg/mL exceeds the therapeutic range (10-20 mcg/mL), indicating potential toxicity.
- Albumin Level: Sheila's low albumin level of 2 g/dL can impact the interpretation of the total Dilantin level. Calculating the corrected Dilantin level using the Sheiner-Tozer equation is essential to adjust for hypoalbuminemia and obtain an accurate representation of free, active drug levels.
Treatment Plan
1. Immediate Management:
- Discontinue Dilantin: Cease Sheila's Dilantin to prevent further accumulation and mitigate toxicity.
- Monitor Vital Signs: Regularly assess vital signs and neurological status to monitor for potential complications.
2. Corrected Dilantin Level Calculation:
- Corrected Dilantin Level Calculation:- Equation: Corrected Phenytoin Level (mcg/mL) = Total Phenytoin Level / ((0.2 x Albumin) + 0.1)
- Calculate the corrected Dilantin level to guide subsequent management decisions.
3. Initiation of Alternative Antiepileptic Medication:
- Levetiracetam (Keppra):- Prescription Order: Levetiracetam 500 mg PO BID
- Rationale: Levetiracetam is a well-tolerated antiepileptic medication with a low risk of drug interactions and toxicity, making it a suitable alternative for seizure control in the setting of Dilantin toxicity.
4. Neurology Consultation and Follow-Up:
- Referral to Neurology: Coordinate a consultation with a neurologist to assess Sheila's seizure control, adjust her antiepileptic regimen, and provide ongoing management.
- Educate Patient: Provide Sheila with detailed information on her medication regimen, potential side effects, and the importance of compliance with follow-up appointments.
Sources:
1. Epilepsy Foundation. (2021). Seizure First Aid and Safety.
2. American Academy of Neurology. (2020). Evidence-Based Guideline Update: Pharmacologic Treatment for Epilepsy.
3. U.S. National Library of Medicine. (2021). Phenytoin Toxicity.
By promptly recognizing and addressing Dilantin toxicity in Sheila, healthcare providers can ensure appropriate management of her symptoms, prevent potential complications, and optimize seizure control with alternative antiepileptic therapy. Collaborative care involving neurology consultation, monitoring of corrected medication levels, and patient education is essential in managing this clinical scenario effectively and promoting Sheila's overall well-being.