Photosensitivity reactions caused by lomefloxacin hydrochloride: a multicenter survey

Photosensitizing Medications and Skin Cancer: A Comprehensive Review

(1) The incidence of skin cancer is increasing in the United States (US) despite scientific advances in our understanding of skin cancer risk factors and treatments. In vitro and in vivo studies have provided evidence that suggests that certain photosensitizing medications (PSMs) increase skin cancer risk. This review summarizes current epidemiological evidence on the association between common PSMs and skin cancer. (2) A comprehensive literature search was conducted to identify meta-analyses, observational studies and clinical trials that report on skin cancer events in PSM users. The associated risks of keratinocyte carcinoma (squamous cell carcinoma and basal cell carcinoma) and melanoma are summarized, for each PSM. (3) There are extensive reports on antihypertensives and statins relative to other PSMs, with positive and null findings, respectively. Fewer studies have explored amiodarone, metformin, antimicrobials and vemurafenib. No studies report on the individual skin cancer risks in glyburide, naproxen, piroxicam, chlorpromazine, thioridazine and nalidixic acid users. (4) The research gaps in understanding the relationship between PSMs and skin cancer outlined in this review should be prioritized because the US population is aging. Thus the number of patients prescribed PSMs is likely to continue to rise.

Photosensitivity induced by lomefloxacin versus other fluoroquinolones: A meta-analysis

Lomefloxacin may be more likely than other fluoroquinolones to cause photosensitivity. However, the rate of photosensitivity is variable and a meta-analysis has yet to be performed. The aim of this meta-analysis is to compare the rate of photosensitivity between outpatients who received lomefloxacin and those who received other fluoroquinolones. PubMed, EMBASE, Cochrane Library databases and trial registries were searched for randomized controlled trials (RCTs) of outpatients through June 12, 2019. The study outcome was the rate of photosensitivity based on the intention-to-treat principle, estimated by risk difference (RD) as the primary analysis and Peto odds ratio (Peto OR) as the secondary analysis, with 95% confidence intervals (CIs) using random-effects models. Four RCTs (total of 2295 patients) were included in this meta-analysis. A statistically higher risk of photosensitivity was found with lomefloxacin than with other fluoroquinolones (RD, 3.4%; 95% CI, 0.7%-6.2%; P-value = 0.013; I² = 10.9%). The odds of photosensitivity was also significantly higher with lomefloxacin (Peto OR, 5.81; 95% CI, 3.34 to 10.11; P-value <0.001; I² = 0%). This meta-analysis of RCTs found significantly higher photosensitivity with lomefloxacin compared to other fluoroquinolones. Considering this finding and given its lack of additional efficacy compared to other fluoroquinolones, lomefloxacin as a fluoroquinolone option should potentially be reconsidered.

Drug-Induced Photosensitivity-An Update: Culprit Drugs, Prevention and Management

Photosensitive drug eruptions are cutaneous adverse events due to exposure to a medication and either ultraviolet or visible radiation. In this review, the diagnosis, prevention and management of drug-induced photosensitivity is discussed. Diagnosis is based largely on the history of drug intake and the appearance of the eruption primarily affecting sun-exposed areas of the skin. This diagnosis can also be aided by tools such as phototesting, photopatch testing and rechallenge testing. The mainstay of management is prevention, including informing patients of the possibility of increased photosensitivity as well as the use of appropriate sun protective measures. Once a photosensitivity reaction has occurred, it may be necessary to discontinue the culprit medication and treat the reaction with corticosteroids. For certain medications, long-term surveillance may be indicated because of a higher risk of developing melanoma or squamous cell carcinoma at sites of earlier photosensitivity reactions. A large number of medications have been implicated as causes of photosensitivity, many with convincing clinical and scientific supporting evidence. We review the medical literature regarding the evidence for the culpability of each drug, including the results of phototesting, photopatch testing and rechallenge testing. Amiodarone, chlorpromazine, doxycycline, hydrochlorothiazide, nalidixic acid, naproxen, piroxicam, tetracycline, thioridazine, vemurafenib and voriconazole are among the most consistently implicated and warrant the most precaution by both the physician and patient.

UV-Vis spectrophotometrical and analytical methodology for the determination of singlet oxygen in new antibacterials drugs

We have determined and quantified spectrophotometrically the capacity of producing reactive oxygen species (ROS) as (1)O(2) during the photolysis with UV-A light of 5 new synthesized naphthyl ester derivates of well-known quinolone antibacterials (nalidixic acid (1), cinoxacin (2), norfloxacin (3), ciprofloxacin (4) and enoxacin (5)). The ability of the naphthyl ester derivatives (6-10) to generate singlet oxygen were detecting and for the first time quantified by the histidine assay, a sensitive, fast and inexpensive method. The following tendency of generation of singlet oxygen was observed: compounds 7 > 10 > 6 > 8 > 9 >> parent drugs 1-5.

UV-Vis Spectrophotometrical and Analytical Methodology for the Determination of Singlet Oxygen in New Antibacterials Drugs

We have determined and quantified spectrophotometrically the capacity of producing reactive oxygen species (ROS) as 1O2 during the photolysis with UV-A light of 5 new synthesized naphthyl ester derivates of well-known quinolone antibacterials (nalidixic acid (1), cinoxacin (2), norfloxacin (3), ciprofloxacin (4) and enoxacin (5)). The ability of the naphthyl ester derivatives (6-10) to generate singlet oxygen were detecting and for the first time quantified by the histidine assay, a sensitive, fast and inexpensive method. The following tendency of generation of singlet oxygen was observed: compounds 7 >10 > 6 > 8 > 9 >> parent drugs 1-5.

New Findings on the Structure-Phototoxicity Relationship and Photostability of Fluoroquinolones

The present study examined the phototoxicities of a series of 7-(3-aminopyrrolidinyl) quinolones containing various substituents at position 1 by use of a mouse model. For the 7-(3-aminopyrrolidinyl) quinolones with a halogen atom at position 8, well-known substituent groups such as a cyclopropyl, an ethyl, or a difluorophenyl at position 1 were found to be responsible for severe phototoxicity. However, when an aminodifluorophenyl or an isoxazolyl group was placed at position 1, even 8-halogeno quinolones were found to be mildly phototoxic. This is the first report of 8-halogeno quinolones that are not severely phototoxic. Two structurally similar 8-chloro quinolones (the 1-aminodifluorophenyl 8-chloro quinolone and the 1-difluorophenyl 8-chloro quinolone) were investigated further. The former was mildly phototoxic; the latter was severely phototoxic. We demonstrate that these two 8-chloro quinolones have practically the same areas under the concentration-time curves from 0 to 4 h in auricular tissue, suggesting that the mild phototoxicity is not due to pharmacokinetic instability. The rates of UV photodegradation of these compounds were also measured. We found that these two quinolones photodegrade at similar rates, suggesting that the mild phototoxicity is not attained through increased photostability. In conclusion, the phototoxic potentials of fluoroquinolones are influenced not only by the substituent at position 8 but also by that at position 1. We also discovered a mildly phototoxic 8-chloro quinolone which did not have increased photostability.

New findings on the structure-phototoxicity relationship and photostability of fluoroquinolones with various substituents at position 1

The present study examined the phototoxicities of a series of 7-(3-aminopyrrolidinyl) quinolones containing various substituents at position 1 (in which the substituent at R8 is a hydrogen or a halogen) by use of a mouse model. For the 7-(3-aminopyrrolidinyl) quinolones with a halogen atom at position 8, well-known substituent groups such as a cyclopropyl, an ethyl, or a difluorophenyl at position 1 were found to be responsible for severe phototoxicity. However, when an aminodifluorophenyl or an isoxazolyl group was placed at position 1, even 8-halogeno quinolones were found to be mildly phototoxic. This is the first report of 8-halogeno quinolones that are not severely phototoxic. Two structurally similar 8-chloro quinolones (the 1-aminodifluorophenyl 8-chloro quinolone and the 1-difluorophenyl 8-chloro quinolone) were investigated further. The former was mildly phototoxic; the latter was severely phototoxic. We demonstrate that these two 8-chloro quinolones have practically the same areas under the concentration-time curves from 0 to 4 h in auricular tissue, suggesting that the mild phototoxicity is not due to pharmacokinetic instability. The rates of UV photodegradation of these compounds were also measured. We found that these two quinolones photodegrade at similar rates, suggesting that the mild phototoxicity is not attained through increased photostability. In conclusion, the phototoxic potentials of fluoroquinolones are influenced not only by the substituent at position 8 but also by that at position 1 (a new finding from this study). We also discovered a mildly phototoxic 8-chloro quinolone which did not have increased photostability.

Photoinduced N-demethylation of rufloxacin and its methyl ester under aerobic conditions

Irradiation of rufloxacin (RF) under aerobic conditions gives rise to N-demethylation of the piperazinyl ring, which is enhanced in aerated D2O. Two primary processes seem to be involved in RF N-demethylation: photoionization from 1RF and singlet oxygen generation from 3RF. Both processes may lead to the same key intermediates, namely, RF*+ and superoxide radical anion; coupling of these intermediates explains N-demethylation of RF via an iminium cation. Formation of the hydrated electron by a monophotonic process (with a quantum yield of 0.09) is detected along with 3RF (with a intersystem-crossing quantum yield phiISC = 0.36) by laser flash photolysis. Studies performed on RF methyl ester give qualitatively similar results.

Photochemical decomposition of lomefloxacin in vitro and in vivo

To obtain an idea of the photostability of Lomefloxacin (Lom) under in vivo conditions the compound was exposed to UV-A (310-360 nm) in PBS buffer pH 7.4. Exposure of 10 microg/ml of Lom in PBS pH 7.4 led to more than 50% decomposition within 10 min. Loss of the fluorine atom at C-8 and partial breakdown of the piperazine ring occurred. The only two photoproducts formed under these conditions were AEA, 1-ethyl-6-fluoro-1,4-dihydro-7-(2-aminoethyl-amino)-4-oxo-3-quinolinecarboxylic acid, and APA, 1-ethyl-6-fluoro-1,4-dihydro-7-(2-aminopropyl-amino)-4-oxo-3-quinolinecarboxylic acid. When Lom was exposed in whole blood in vitro, the same photochemical decomposition was observed in the plasma as in PBS buffer: APA and AEA were the only products. During UV-A exposure, Lom was shown to be taken up by the leukocytes. This process appeared to be less rapid during UV-A exposure than in the dark. As soon as UV-A exposure commenced, AEA and APA were found. As in the plasma, the total amount of Lom and the two photoproducts in the leukocytes was not significantly different from the amount of Lom found in unexposed cells at the same time point. The erythrocytes did not take up Lom, but exposure of whole blood to Lom and UV-A under the above conditions led to more than 7% haemolysis. Treatment of rats with a combination of Lom and UV-A demonstrated photodecomposition of Lom in vivo. In urine produced during exposure and by the irradiated rats during the twilight period after exposure, a considerable amount of AEA and APA was found. The blood plasma from rats exposed simultaneously to UV-A and Lom proved to contain AEA and APA and, in the leukocytes, APA. This was not the case with animals kept in twilight.