Question

Case Study

As a nurse working on a busy Med-Surg unit, your Nurse Manager approaches you and states that you are getting a new admission.  You call to get report from the ER nurse.  He gives the following information:

The patient’s name is Lisa Trowberg.  She is a 23-year- old female with NKA (No Known Allergies). PMH (past medical history) significant for seizures since 15 years of age.  She was being well controlled on phenytoin (Dilantin) until recently when she began to have breakthrough seizure activity.  About 2 weeks PTA (prior to admission), her significant other of 18 months broke up with her.  Becoming increasingly depressed with diminished appetite resulting in significant weight loss, she started taking St. John’s Wart as per a friend’s recommendation.   She was brought in by ambulance for a grand mal seizure with + urinary incontinence.  En route, she was given diazepam (Valium) IV x 2 doses and is now postictal.  In addition, she was diagnosed with strep pharyngitis 1 day ago and was put on Amoxicillin ERT (Extended Release Tablet) 775 mg to be taken once daily by mouth.  Today is day 2 of this regimen. She weighs 105 lbs.

Medications PTA (Prior to admission):  

• phenytoin (Dilantin) 200 mg po BID,
• Amoxicillin ERT 775 mg po qd x 3 days
• ethinyl estradiol/drospirenone (Yaz) 20 mcg/3mg  1c tablet daily according to package,
• St. John’s Wort (Rosin Rose) 300 mg po TID,
• Ibuprofen (Motrin) 600 mg po q6 prn fever or sore throat.

Her current V/S are BP 110/60  HR 74   RR 14   T 101.4°F  

CHEM-7 LABS:

Na:139

K:4.1

Cl: 102

HCO3: 23

BUN: 18

Cr: 0.7

GLU: 78

phenytoin: 5.2

Albumin:  2.4

Her admission orders are:

• V/S q4h
• Seizure precautions,
• NPO except for meds
• IVF of D5 ½ NS with 20 mEq KCl/L Infuse 2.5 liters of ordered IVF over 24 h
• Amoxicillin ERT 775 mg daily by mouth for 2 more days then discontinue
• ethinyl estradiol/drospirenone (Yaz) 20 mcg/3mg, give 1 tab daily according to package
• Phenytoin (Dilantin) 200 mg twice a day by mouth
• St. John’s Wort (Rosin Rose) 300 mg orally three times per day – pt may use her own once verified by pharmacy
• Ibuprofen (Motrin) 1000 mg by mouth q6h prn T>100.5°F

BONUS QUESTIONS

A. Which alternate medication(s) would you suggest to the provider to prescribe to your patient and why?

B. What patient teaching would you offer to this patient?

THIS IS ALL THE INFORMATION I WAS PROVIDED. CAN SOMEONE PLEASE HELP WITH THESE TWO QUESTIONS THANK YOU.

Answer 1

As per the given data I would recommend -

1. To discontinue  St Johns Worts as it is over the counter medication ( herbal supplement), and its results on depression are mixed. It decreases blood level of Phenytoin ( Dilantin), there by interfering with seizure control in patients on Phenytoin.

As patients seizures was well controlled before taking St Johns Wort tablets, there are high chances of this interaction.

Another important consideration is that depression is a common but serious mental health issue and one should seek professional help when in need. St. Johns Wort is not a standard treatment for depression.

2. I would like to add Folic acid supplement 5 mg daily , as folic acid deficiency is common in patients on Phenytoin.

3. Since now patient is NPO but if in case started with entral feeding do not give Phenytoin concomitantly with feeds. Better to give empty stomach once in a day at same time daily to maintain consistent blood level.

4. Normal therapeutic range of Phenytoin is 10-20 micro gram per milliliter. However this range is a rough guide and need to be needs to be individualized according to how well  seizure are controlled. Since the patients Phenytoin level is on lower side but may be due to St. Johns Worts. Also the patients BUN and Creatinine are in normal range indicating that renal function has not compromised. So will recommend regularly monitoring of blood Phenytoin after discontinuation of St. Johns Wort, and if needed will consider readjustment of dosages.

5. Another recommendation is regarding patients contraceptive use. Phenytoin reduces efficacy of hormonal contraceptives, specially Ethinyl Estradiol by increasing their metabolism, so need either a higher dose nearly 50 microgram per day to compensate enhanced metabolism or should switch to other hormonal contraceptives like Levonorgestrel intrauterine system (hormonal intrauterine device) or subcutaneous Medroxy progesterone acetate preparations