Question: Dear Doctor ,
My mother ( an 82 year-old of South Asian descent with FT Dementia since the last 20 years) had a biopsy for a suspected case of Bullous Pemphigoid back in January of this year. The Dermatologist started my mother on Prednisone 5 mg, (as well as topical Betadone crème) starting with 8 tablets per day and reducing every two weeks by one tablet. My mother’s rash and blisters have completely disappeared and she is in the process of tapering off the medication. However, when I reduced her from 4 tablets per day (20 mg) to 3, she started having vigorous muscular twitches (tics) and seizures; as soon as I put her back on 4 tablets, the seizures stopped.

My mother has been on Valproic acid for seizure activity for the last five years. The original cause for which the neurologist prescribed the Valproate was an episode in which she had violent shaking of the legs and hands and had to be turned on her side to breathe; the seizure lasted about five minutes. Since then, she has had seizures only once or twice per year, usually after she has had difficulty breathing due to a congested nasal passage or after she has had low circulation. The dose she has been taking is 5mL per day. However, around the same time that she developed the Bullous Pemphigoid, I have observed she is having more difficulty taking the Valproate. Particularly when I attempt to give her all 5mL at once, her nose fills up with mucus, she starts to cough and her eyes water. She does not have any pathology with her swallowing mechanism, as confirmed by a hospital test.
I have noticed that if I do not give her the Valproate for several days, she is fine and does not exhibit any tic activity. However, if after the few days of abstention I give her the Valproate again, at the prescribed or lower dose, the seizure and tics come back. The same pattern occurs with the prednisone; she seems to be fine being off it completely but if she goes back on at the lower dose, the seizure activity returns.

Thus, the Dermatologist recommended that my mother continue taking 4 tablets of prednisone (20mg) per day until she sees a neurologist, especially to undergo a CT scan to determine if there is any inflammation on the brain that the prednisone may be suppressing.

My questions to you are:
1.     Could the prednisone be the cause of the seizure activity?
2.     Could my mother have developed an allergy to the Valproate (which could also have mimicked the symptoms of Bullous Pemphigoid)?

I am awaiting a consult with her neurologist, but was hoping you could shed some light on this puzzle in the meanwhile.
Sincere thanks,
XXXXXXX