Tranexamic Acid-Induced Fixed Drug Eruption.

A 33-year-old male showed multiple pigmented patches on his trunk and extremities after he took tranexamic acid for common cold. He stated that similar eruptions appeared when he was treated with tranexamic acid for influenza 10 months before. Patch test showed positive results at 48 h and 72 h by 1% and 10% tranexamic acid at the lesional skin only. To our knowledge, nine cases of fixed drug eruption induced by tranexamic acid have been reported in Japan. Tranexamic acid is a safe drug and frequently used because of its anti-fibrinolytic and anti-inflammatory effects, but caution of inducing fixed drug eruption should be necessary.

What was known?

Tranexamic acid is frequently used for skin pigmentation such as melasma. To date, only several cases of fixed drug eruption induced by tranexamic acid have been reported.

Introduction

Tranexamic acid is an anti-fibrinolytic agent. In the field of dermatology, tranexamic acid is effective for ultraviolet-induced melasma. We describe herein a case of fixed drug eruption induced by tranexamic acid.

Case Report

A 33-year-old male was referred to our department, complaining of multiple pigmented patches on his trunk and extremities, which appeared 17 days previously. Clarithromycin, tranexamic acid, l-carbocisteine, and bifidobacterium were prescribed for common cold. Within 1 hour after taking these drugs, pruritic eruption appeared. Ten months previously when he got influenza, he was treated with oseltamivir, tranexamic acid and dextromethorphan hydrobromide hydrate. He stated that similar eruptions appeared then. Physical examination revealed several oval brownish pigmented patches on his upper extremities, right dorsum of foot, and waist [Figure 1]. He refused biopsy examination. Patch test was performed with 1% and 10% of clarithromycin, tranexamic acid, l-carbocisteine, bifidobacterium, oseltamivir and dextromethorphan hydrobromide hydrate in petrolatum on the lesional and non-lesional skin. Results showed erythematous reaction at 48 h and 72 h by 1% and 10% tranexamic acid at the lesional skin only [Figure 2]. Other drugs-applied sites did not show positive reactions.

Figure 1

Oval pigmented macule on the forearm

Figure 2

Results of patch test showing positive reaction of 1% and 10% tranexamic acid at the applied sites of pigmented patches

Discussion

Tranexamic acid is frequently used for melasma in dermatology clinics. The efficacy of oral tranexamic acid for skin pigmentation is well known. In vivo studies have shown that intradermal injection of tranexamic acid did not reduce the number of melanocytes in the ultraviolet irradiated skin. They speculate that tranexamic acid affects the function by inhibiting melanin production. To date, fixed drug eruption caused by tranexamic acid is rarely reported in English literatures.[1] Fixed drug eruption appears as solitary or multiple well-circumscribed, rounded erythematous macules. The pathogenesis of fixed drug eruption is not fully elucidated as yet; however, the resting lesions of previously affected sites contain a number of CD8-positive T cells in the basal layers of the epidermis, which play a major role in the epidermal injury via interferon-γ (IFN-γ).[2]

Our case had similar episodes twice. He took several kinds of medicine, and only tranexamic acid was common in both episodes. Results of patch test showed positive reaction at the applied sites on the pigmented macule. Therefore, we concluded that tranexamic acid induced fixed drug eruption although we did not carry out the challenge test. To our knowledge, nine cases of fixed drug eruption induced by tranexamic acid have been reported in Japan including the presented case, which are summarized in Table 1. Patients were three males and six females, and the age ranged from 5 to 74 years old. All cases presented with multiple lesions on the trunk, extremities and face. Patch test was performed in six cases, among which only two cases showed positive reaction, which may suggest that the ratio of positive patch test reaction of this drug is not high. Cases with negative results in patch test were diagnosed by the challenge test. Tranexamic acid is a safe drug and frequently used because of its anti-fibrinolytic and anti-inflammatory effects, but caution of inducing fixed drug eruption should be necessary.

Table 1

Characteristics of patients with fixed drug eruption due to tranexamic acid

What is new?

We are reporting a rare case of fixed drug eruption induced by tranexamic acid, as well as reviewing the literatures of previous works.