Fluorouracil
A fluorinated pyrimidine called fluorouracil (5-FU) functions as an antimetabolite antineoplastic agent. It varies from uracil, a naturally occurring substance, by having a fluoride added at position 5. For many solid tumors, including breast, colorectal, gastrointestinal, and head and neck malignancies, fluorouracil is a part of chemotherapy regimens. The pharmacokinetics of 5-FU are compounded by intra- and inter-patient variability, nonlinear elimination, and inconsistent bioavailability, which add to the drug’s complex clinical pharmacology. The drug’s delivery route affects the drug’s toxicities and effectiveness. In a meta-analysis of 5-FU studies for the treatment of colorectal cancer, it was discovered that continuous infusion was superior to bolus injection in terms of response and overall survival rate, with a lower incidence of severe hematologic toxicity. However, compared to the bolus injection, the continuous infusion had a higher prevalence of hand-foot syndrome. 1 Although it is frequently administered intravenously, fluorouracil can also be applied topically to treat malignant skin keratoses. The FDA granted fluorouracil approval in 1962. The FDA authorized CaracTM, a novel fluorouracil cream formulation that uses a microsponge delivery mechanism. The novel delivery mechanism enables a prolonged release of fluorouracil and a single daily dose.

Salicylic Acid
A topical keratolytic agent is salicylic acid. In hyperkeratotic skin conditions such plantar and common warts, psoriasis, seborrheic dermatitis, calluses, and corns, it is used to eliminate extra keratin. Acne can also be treated with salicylic acid. Salicylic acid functions by inducing the horny layer of skin to desquamate. Salicylism may be caused by prolonged or daily application across broad areas of skin, especially in youngsters and people with renal or hepatic impairment. The FDA authorized this medication in 1939. 23456789