Erythema multiforme, target lesions

I am 61 years old and have had FMS for 15 years.  I have fought the fight and was winning, or so I thought.  I do not have diabetes; I am normal weight and blood pressure and cholesterol.  I live a good life and am able to do the things I want to do.  However, I have broken out with target lesions (erythema multiforme).  They started to appear last November.  I have had a biopsy done and it only told me that I do not have skin cancer or a fungus infection.  The docs (I have 2 working on it both GP's since we have long waiting lists to see specialists in Canada: I am on the list to see a dermatologist in September) both thought that it might be meds or supplements.  I was taking 30 mgs of Amitriptyline for sleeping, Conjugated Estrogens (.625) and 200 mgs of Gabapentin a day along with a lot of supplements: a one a day vitamin, 250 mgs of magnesium, 800 IU's of vitamin D along with MSM, SAMe, 3 mgs of melatonin (with the Amitriptyline at bed time) etc., etc.  

The docs took me off all supplements and pared me right down on meds.  I went on 20 mgs of Amitriptyline (a lifesaver, literally) and nothing else.  Well, the lesions did not go away, I started out with 5 and now have 16.  I started getting hot flushes again and so much pain in my legs that I could not sleep more than an hour at a time even with the Amitriptyline.  My life went back to square 1 with the fibromyalgia.  I was so tired and irritable and in so much distress that I could not live with myself: never mind the others around me.

I went back to one of the docs (I have one in Yukon where we are residents and one in British Columbia where we go in winter now that we are retired) and he put me back on conjugated estrogens (one every other day) and 200 mgs of Gabapentin (one in the morning and one in the evening for sleeping).  The change was remarkable.  I turned right around in 2 days.  So, I guess there is no question that these drugs help me.  I am still left with the lesions.  Does anyone else out there have this problem and if so, what was causing them?

[sandee1818]

Possible causes
In the past, erythema multiforme was thought to be a cutaneous reaction to a variety of inciting factors, including infections and medications. Several lines of evidence now support the conclusion that most cases, particularly when there is recurrence, are associated with HSV infection. A study of 65 patients with recurrent erythema multiforme found that 46 (71%) had experienced HSV infection in the 3 weeks preceding the episode (4). Most cases were labial HSV infection, and the average interval to development of erythema multiforme was 8 days.

Studies using polymerase chain reaction have detected HSV DNA in biopsy samples of erythema multiforme lesions (5,6) and even at the site of healed lesions (6). The test has documented HSV DNA in skin lesions of HSV-associated erythema multiforme and idiopathic erythema multiforme (ie, disease with no known underlying inciting condition) but not in lesion-free skin (7).

A double-blind, placebo-controlled study found that a 6-month course of acyclovir (400 mg twice daily) suppressed recurrences, even in idiopathic disease, further supporting the theory that recurrent disease may be related to subclinical HSV infection (8). Although it is unclear why HSV infection precipitates recurrence in only a fraction of patients, studies have found an increased frequency of certain HLA antigens in association with recurrent disease (9), suggesting that genetic factors may play a role. Areas for further investigation include how HSV infection precipitates recurrence and why it occurs in certain patients.

Other potential causes of erythema multiforme include malignant tumors, hormonal factors (1,4), infections other than HSV (10), and medication use (3). Past reviews have emphasized medications as a cause of erythema multiforme, but supporting evidence is unclear, and how often this truly occurs is uncertain. Idiopathic cases remain and are a source of frustration for patients and physicians.