AN OPTION IN COMBINATIONS OF CORTICOSTEROIDS WITH ANTIMICROBIAL AGENTS: VIOFORM
Dear colleagues, although combinations of corticosteroids with antimicrobial agents are rarely indicated and their use is limited, if a combination is nonetheless required and an adjunctive treatment to the corticosteroid must be administered, we can count Clioquinol among the agents that may be preferred.
Clioquinol, also commonly known as Vioform, is indicated in conditions where secondary bacterial and/or fungal infections are present, suspected, or anticipated; and has been used for many years in combination with cortisones in the treatment of diseases such as eczemas including atopic, infantile, and discoid types, prurigo nodularis, psoriasis (excluding widespread plaque types), lichen planus, neurodermatoses including lichen simplex, seborrheic dermatitis, contact sensitivity reactions, insect bite reactions, prickly heat (miliaria), anal or genital intertrigo, and external ear inflammation (otitis externa). The preparation is also used in otitis externa where the microorganism is sensitive to clioquinol. Although its use has decreased in recent years due to the availability of better pharmacotherapeutic alternatives, it continues to be prescribed by physicians. Clioquinol frequently causes sensitization. Because clioquinol is absorbed through the skin over large surface areas, cutaneous use in children is not recommended. It also causes discoloration of the skin, clothing, and linens.
Vioform, Chinoform, Iodochlorhydroxyquin, Chloroiodoquin, Clioquinolum [INN; Ph. Helv. 8], Chloroiodoquine [DCF];
Clioquinol is a halogenated hydroxyquinoline compound exhibiting antibacterial and antifungal activity. It is incorporated into the formulation of creams and ointments used for the treatment of skin infections. In these preparations, it is predominantly present at a concentration of 3%. Combined preparations with a corticosteroid are available, particularly for the treatment of inflammatory skin diseases complicated by bacterial or fungal infections. The antimicrobial mechanism of action of clioquinol is not well defined. Clioquinol can alter the distribution of metals in cells by chelating and sequestering metals at the cell membrane. This may lead to a general deficiency of transition metal ions for most metalloproteins. When clioquinol is applied topically to the skin, it can be absorbed into the systemic circulation. This property is significant because it exerts neurotoxic effects systemically. Therefore, the use of clioquinol in infants and young children should be avoided. The half-life of systemic clioquinol is 11–14 hours. Following topical application, a serum half-life of 19–30 hours has been demonstrated, with a reduction in half-life if zinc ointment is used (9–14 hours). Based on a small pharmacokinetic study of topically applied clioquinol, absorbed clioquinol is metabolized into sulfates (3.8 ± 3%) and glucuronides (96 ± 3%). It is excreted as free drug and as glucuronide and sulfate metabolites. Another small pharmacokinetic study showed that urinary excretion was 2.2–7.5% of the topically applied dose over 30–70% of the body surface area daily (corresponding to 0.48–0.98 g/day), and that 95% of the total excreted amount consisted of conjugated metabolites.
Clioquinol is a bulky powder varying in color from yellowish-white to brownish-yellow, with a characteristic odor slightly reminiscent of saffron. It darkens upon exposure to light. It is practically insoluble in water; soluble 1:3500 in alcohol, 1:120 in chloroform, and 1:4500 in ether; freely soluble in dimethylformamide and pyridine; soluble in hot ethyl acetate and hot glacial acetic acid. Aqueous creams containing clioquinol exhibit incompatibility with aluminum. They are degraded by oxidizing agents. Clioquinol can stain underwear and bed linens. Clioquinol should be stored at room temperature below 30°C and in airtight containers. It must be protected from light. Its antiseptic property is stronger than that of iodoform, with the advantages of being odorless and non-toxic. It is used in powder form to treat epidermophytosis (tinea pedis) of the feet. It has been used in ophthalmic ointments for corneal wounds, keratitis, etc. It is also effective in eczema, burns, and varicose ulcers.
FORMULA:
Rx.
Tumenol 5 g
Vioform 2 g
Zinc oxide 10 g
Liquid petrolatum 40 g
Preparation of the formula:
Triturate the vioform with zinc oxide into a fine powder, add tumenol, and form a paste. Gradually add the liquid petrolatum to this mixture. Store in an opaque container to protect from light.
FORMULA:
For the treatment of fungal infections in the external ear canal, Clioquinol Ear Drops 1%
Rx.
Clioquinol 1 g
Polyethylene glycol 400 ad 100 g
FORMULA:
In acute otitis externa, in secondarily infected inflammatory conditions of the auditory canal, it is applied into the ear canal in the form of an ear wick/tampon.
Rx.
Clioquinol 1 g
Triamcinolone acetonide 100 mg
Polyethylene glycol 400 ad 100 g
FORMULA:
This preparation is used in infected inflammatory dermatoses.
Rx.
Hydrocortisone acetate 1 g
Clioquinol 3 g
Lanolin 10 g
Petrolatum 86 g
Source:
1-La Formulación Magistral en la Oficina de Farmacia valencia, 1981
2–Formularium der Nederlandse Apothekers 2009
3–Rx MediaPharma®2023 Interactive Drug Information Source
Exp. Pharm. Ahmet Nezihi Pekcan
Konya 12.03.2023
