ATC Group: C05A Agents for treatment of hemorrhoids and anal fissures for topical use

Benzocaine is a local anaesthetic of the ester type, acting to produce reversible loss of sensation by preventing or diminishing the generation and transmission of sensory nerve impulses near the site of application. Depolarisation of the neuronal membrane and ion exchange are reversibly inhibited.

Betamethasone is a glucocorticoid which is about eight to ten times as active as prednisolone on a weight-for-weight basis. Betamethasone has anti-inflammatory, antipruritic, and vasoconstrictive properties.

Cinchocaine is a local anaesthetic agent and is suitable for surface or spinal anaesthesia and for relaxing sphincteric spasms. It is an anaesthetic of the amide type. It is more toxic than cocaine by local application but its local anaesthetic action is greater so it can be used in lower concentrations. Its action is more prolonged than lignocaine.

Dexamethasone is a synthetic glucocorticoid; it combines high anti-inflammatory effects with low mineralocorticoid activity. It has an approximately 7 times greater anti-inflammatory potency than prednisolone, another commonly prescribed corticosteroid. At high doses it reduces the immune response.

Diltiazem is a calcium antagonist. It restricts the slow channel entry of calcium into the cell and so reduces the liberation of calcium from stores in the sarcoplasmic reticulum. This results in a reduction of the amount of available intracellular calcium reducing myocardial oxygen consumption.

Fluocinolone acetonide is a synthetic fluorinated corticosteroid with anti-inflammatory, antipruritic, and vasoconstrictive properties.

Fluocinonide is a synthetic anti-inflammatory corticosteroid. Its mechanisms of action are related to vasoconstriction and suppression of membrane permeability, mitotic activity, the immune response and release of inflammatory mediators.

Fluocortolone pivalate inhibits inflammatory and allergic skin reactions, and alleviates subjective complaints such as pruritus, smarting, and pain. The substance reduces dilatation of the capillaries, oedema of the interstitial cells and infiltration of the tissues. Capillary multiplication is inhibited.

Fluorometholone is a synthetic corticosteroid (glucocorticoid), a derivative of desoxyprednisolone. It is a member of the group of universally known steroids used for the treatment of eye inflammation. Glucocorticosteroids bind to cytoplasmic receptors and control the synthesis of infection mediators thus damping inflammatory reactions (swelling, fibrin deposition, capillary dilatation, phagocyte migration) and also capillary proliferation, collagen deposition and scarring.

Glyceryl trinitrate is a vasodilator and is used for angina of effort. Vasodilation is achieved by the releasing of free redical nitric oxide which activates guanylate cyclase and increases synthesis of guanosine 3′ and 5′-monophosphate with resultant effects on the phosphorylation of proteins in smooth muscle. If taken in excess, its vasodilatory effect can cause headache.

Hydrocortisone is the main glucocorticoid secreted by the adrenal cortex. Hydrocortisone is an anti-inflammatory steroid. Its anti-inflammatory action is due to reduction in the vascular component of the inflammatory response and reduction in the formation of inflammatory fluid and cellular exudates.

Isosorbide dinitrate is an organic nitrate, which in common with other cardioactive nitrates, is a vasodilator.

Lidocaine, like other local anaesthetics, causes a reversible blockade of impulse propagation along nerve fibres by preventing the inward movement of sodium ions through the nerve membrane. Local anaesthetics of the amide-type are thought to act within the sodium channels of the nerve membrane.

Oxetacaine is a potent surface analgesic with the molecular formula N, N-bis-(N-methyl-N-phenyl-t-butyl-acetamide)-beta-hydroxyethylamine that conserves its unionized form at low pH levels. Its actions have shown to relieve dysphagia, relieve pain due to reflux, chronic gastritis, and duodenal ulcer.

Phenylephrine is a sympathomimetic agent with mainly direct effects on adrenergic receptors. It has predominantly alpha adrenergic activity and is without stimulating effects on the central nervous system. The sympathomimetic effect of phenylephrine produces vasoconstriction which in turn relieves nasal congestion.

Prednisolone is a glucocorticoid which has anti-inflammatory activity. Naturally occurring glucocorticoids (hydrocortisone and cortisone), which also have salt-retaining properties, are used as replacement therapy in adrenocortical deficiency states. Their synthetic analogs are primarily used for their potent anti-inflammatory effects in disorders of many organ systems.

Procaine is a benzoic acid derivative with local anesthetic and antiarrhythmic properties. Procaine binds to and inhibits voltage-gated sodium channels, thereby inhibiting the ionic flux required for the initiation and conduction of impulses. In addition, this agent increases electrical excitation threshold, reduces rate of rise of action potential and slows nerve impulse propagation thereby causing loss of sensation. Procaine is indicated for production of local or regional anesthesia, particularly for oral surgery. Procaine (like cocaine) has the advantage of constricting blood vessels which reduces bleeding, unlike other local anesthetics like lidocaine.

Tetracaine is a local anaesthetic and is believed to act by blocking nerve conduction mainly by inhibiting sodium ion flux across the axon membrane.