# Natural Photosensitizers in Clinical Trials
## 3 Natural Photosensitizers in Clinical Trials
### Anthraquinones
\begin{table}
\begin{tabular}{c c c} \hline
**Photosensitizer** & **Therapeutic Regimen** & **Findings** & **Article** \\ \hline Application of 0.25\% hypericin ointment to each index lesion, covering it with an opaque dressing or clothing for 18 to 24 h, followed by exposure to visible light in the range of 500 to 650 nm; Light treatment started at 5 J/cm\({}^{2}\) and increased by 1 J/cm\({}^{2}\) with each treatment, until a mild skin reaction was observed in the treated lesions or until a maximum light dose of 12 J/cm\({}^{2}\) was reached. Lesions were treated twice a week for each 6-week cycle & Achieving 49\% success rate in \\  & \\ \hline Application of hypericin ointment with a concentration of 2 mg/mL to the lesion and 10 mm of surrounding skin in a layer 1 mm thick under an occlusive dressing, removing it after 2 h, and irradiating the area with a PDT lamp emitting incoherent red light with a wavelength of 580 to 680 nm. The total light dose was 75 J cm\({}^{2}\) for 15-20 min. The aforementioned lesions were treated with PDT at weekly intervals; the average treatment period was 6 weeks. The number of PDT treatments depended on the clinical features of the treated areas and persistent fluorescence during photodynamic diagnosis. & [PERSON] et al. \\ \hline Application of 1.5 mL of 0.5\% _H. perforatum_ & \\ extract containing 0.1\% hypericin to half of the face for 10 min under occlusion. The face was then illuminated simultaneously with 630 nm red light and 520 nm green light from a 35 mW/cm\({}^{2}\) LED light-emitting device for 10 min (total light dose was 21 J/cm\({}^{2}\)). Participants received a total of four treatments at 1-week intervals and were observed 1 and 4 weeks after the last treatment. & Come week after the last PDT treatment with _H. perforatum_ extract, a 56.5\% reduction in acne lesions was observed. & [PERSON] et al. [56] \\  & \\ \hline Ref pretreatment of PEEK posts and exposure to light at 632 nm, 150 mW power, and power density of 23.43 J/cm\({}^{2}\) continuously for 1 min & RF-PDT can be an effective surface conditioner for PEEK inserts & [PERSON] et al. [63] \\  & \\ \hline Riboflavin &
\begin{tabular}{c} RP-PDT showed significantly lower \\ bond integrity values than the other \\ methods tested in the force test of \\ PES \\ \end{tabular} & [PERSON] et al. \\  & \\ \hline \end{tabular}
\end{table} 
Table 2: _Cont._Figure 3: Figure showing natural photosensiers in clinical trials—their example source, structural formula, and the subjects of the clinical trials in which they were used. Explanation: c.t. stands for clinical trial/trials. (1) curcumin, the source of which is, e.g., _Curcum longa_ that was tested in seven clinical papers in oral disinfection (35; 36; 37; 38; 39) and in dental (40) and acne treatments (41); (2) hypericin, the source of which is, e.g., _Hypercium perforatum_ that was tested in three clinical papers in the  
treatment of skin cancers, precancerous conditions and dermatoplytosis [54; 55], and acne [56]; (3) riboflavin, the source of which is, e.g., green vegetables that were tested in three clinical papers in dentistry [63; 64; 65]; (4) phycocyanin, the source of which is, e.g., cyanobacteria that were tested in one clinical paper in dentistry [74]; (5) emodin anthraquinone, the source of which is, e.g., plants of the family _Rubiaceae_ that were tested in one clinical paper in wound healing after gingival transplantation [82].