Action and mechanism

Etofenamate is a non-steroidal [ANTI-INFLAMMATORY] and [ANALGESIC] that acts by preventing the synthesis of prostaglandins and other prostanoids by inhibiting cyclooxygenase, which is involved in inflammatory processes.

Pharmacokinetics

- Absorption: The bioavailability of products containing etofenamate is subject to large inter- and intra-individual fluctuations, resulting primarily from the site of administration, skin hydration, and other factors. Following cutaneous administration, bioavailability, i.e., the proportion of the dose systemically available, is within the range of other products containing etofenamate (greater than 20%).

- Metabolism and Elimination: Etofenamate is excreted as multiple metabolites (hydroxylation, ester and ether cleavage) and their conjugates, 35% via the kidneys and a large proportion via bile and feces. Enterohepatic circulation is highly likely.

Indications

Symptomatic local relief of painful or inflammatory conditions of traumatic or degenerative origin in the joints, tendons, ligaments and muscles ([ARTHRITIS], periarthritis, arthrosinovitis, [TENOSYNOVITIS], [CONTUSION], distortions, [DISLOCATION], meniscal injuries of the knee, [TORTICOLLIS], [LOW BACK PAIN], [SPRAIN], [CONTRACTURE], [BURSITIS], [CAPSULITIS], [TENDINITIS]).

Posology

- For external cutaneous use only.

- Adults and children over 12 years: apply 2 to 3 times a day.

- Do not apply for more than 7 consecutive days without consulting a doctor.

Rules for correct administration

- Apply a thin layer of the product to the affected area with a light massage to facilitate penetration.

- Wash your hands after each application.

- Do not apply occlusive dressings.

Contraindications

- Hypersensitivity to etofenamate or any of the components of this medicine.

- [NSAID ALLERGY], [SALICYLATE ALLERGY]: Although local administration minimizes the risks derived from its systemic use, topical application, in large areas of the skin, in open wounds, mucous membranes or eczematous skin, for a prolonged period and with the use of occlusive dressings, can cause systemic effects, so it is worth remembering that its use is not recommended in patients who have presented allergic reactions (rhinitis, asthma, pruritus, angioedema, urticaria, shock or others), caused by acetylsalicylic acid or other NSAIDs due to the possibility of cross-hypersensitivity.

Precautions

Warnings on excipients:

- This medicine contains dimethyl sulfoxide and may cause skin irritation.

Patient Advice

- Avoid contact with eyes and mucous membranes.

- Do not use with occlusive dressings or apply simultaneously to the same area as other topical preparations.

- Do not use for prolonged periods or on large areas.

- Use only on intact skin, not on open wounds, mucous membranes or eczematous skin.

- Do not expose the treated area to the sun.

- Wash your hands after each application.

Special warnings

- If symptoms persist for more than 7 days or irritation or worsening occurs, the patient's clinical situation should be evaluated.

- Sun exposure of the treated area may cause photosensitivity.

Interactions

They have not been described for cutaneous use, since very low systemic concentrations of the drug are achieved, but it will be assessed whether they should be used in conjunction with other topical analgesics.

Pregnancy

Although systemic absorption is very low when applied cutaneously, the preparation should not be used during pregnancy unless medically indicated, since NSAIDs, especially during the third trimester, can cause dystocia, delay delivery, and cause adverse effects on the fetal cardiovascular system, such as premature closure of the ductus arteriosus.

Lactation

Although systemic absorption is very small when applied cutaneously, the preparation should not be used during breastfeeding unless medically indicated.

Adverse reactions

- Moderate local [ERYTHEMA] (0.1%-1%), [DERMATITIS], local [SKIN IRRITATION], [PRURITUS] (0.1%-1%) and a sensation of [SKIN IRRITATION] may occur in the application area, which disappear when treatment is discontinued.

- [PHOTOSENSITIVITY REACTIONS] may occur (0.01%-0.1%)

- If symptoms appear for which no justification can be found, treatment should be discontinued and the patient's clinical situation should be re-evaluated.

- Prolonged topical administration to large areas of skin, open wounds, mucous membranes, or eczematous skin, as well as the use of occlusive dressings, may cause systemic adverse reactions typical of NSAIDs.

Overdose

- Symptoms: Due to its external use, poisoning is not likely to occur.
In case of accidental ingestion, the symptoms of overdose will be systemic adverse reactions that will depend on the dose ingested and the time elapsed since ingestion.

- Treatment: If accidental ingestion occurs, stomach lavage and symptomatic therapy will be carried out.