Iodoform (CAS 75-47-8), also known as tri-iodomethane, is an organoiodine compound where three hydrogen atoms of methane are replaced by iodine atoms. Discovered by Georges Serullas in 1822, iodoform has a long-standing history in medical formulations due to its antimicrobial and antiseptic properties. Chemically reactive in free radical reactions, iodoform exhibits antimicrobial efficacy when administered topically. The proposed mechanism involves activation by free radicals, leading to the release of iodine, which denatures bacterial proteins and effectively eliminates pathogenic microorganisms. At high concentrations, iodoform also exerts cytotoxic effects on inflammatory cells infiltrating the wound, destroying them and enhancing their therapeutic efficacy.

Bismuth iodoform paraffin paste (BIPP) is the most commonly used form of iodoform, typically supplied as impregnated gauze. Its formulation includes bismuth subnitrate—which acts as an astringent to reduce tissue shrinkage and provides antimicrobial properties—and paraffin, which serves as a lubricant to minimize tissue trauma during packing.

The Effects and Uses of Iodoform and BIPP

Iodoform possesses antimicrobial, antiseptic, and anesthetic properties; it promotes wound healing and facilitates the dissolution of collagen fibers and necrotic tissue. It is widely used in surgery. BIPP was extensively employed to treat gunshot wounds during World War I and has since remained a valuable material for wound packing.

In otolaryngology (ENT) surgery, iodoform (typically in the form of BIPP) is frequently used for postoperative dressings and cavity packing following procedures involving facial bones, the petrous bone, and the paranasal sinuses. BIPP can be left in place within nasal and aural cavities for up to 10 days, providing a sustained antiseptic effect.

In neurosurgery, BIPP is primarily used to pack surgical sites following transsphenoidal or skull-base procedures and to treat chronic, infected scalp wounds. Its efficacy stems from several key characteristics: it renders the impregnated gauze impermeable to blood and body fluids, thereby limiting bacterial nutrients; it stimulates the growth of granulation tissue; and it remains stable even in the presence of necrotic tissue, facilitating clean wound management.

In oral and maxillofacial surgery, iodoform is widely used as an antiseptic material in various surgical interventions.

In general dental practice, iodoform is valued for its antiseptic properties, whether used alone or mixed with eucalyptus oil or glycerin. It is used to treat dry socket, as a dressing for large cystic defects, and as a soft-tissue dressing in cases of wound dehiscence or to promote healing.

Additionally, due to its bismuth content, BIPP is radiopaque—visible on X-rays and CT scans—which facilitates localization.

Toxicity of Iodoform and BIPP

Large amounts of iodoform can be toxic, as it metabolizes into iodine dioxide and produces carbon monoxide—substances that are harmful to the human body. Symptoms of iodoform and iodine toxicity include neuropsychiatric effects, gastrointestinal issues, and cardiovascular symptoms, as well as iodine-specific reactions such as skin rashes, metabolic acidosis, renal failure, reduced white blood cell counts, and thyroid and liver dysfunction.

References

[1] DIA R HALALMEH. Iodoform in Surgical Practice: A Comprehensive Review of Its Historical Evolution, Clinical Applications, and Safety Profiles.[J]. Cureus, 2024, 16 12: e75752. DOI:10.7759/cureus.75752.