Mebucaine

For the rapid relief of pain caused by minor recurrent aphthous mouth ulcers.

Patients hypersensitive to any of the ingredients.

The metabolism of ester-type local anaesthetics may be inhibited by anticholinesterases, increasing the risk of systemic toxicity.

Ester derivatives such as tetracaine, benzocaine, or procaine that are hydrolysed to para-aminobenzoic acid may antagonise the activity of aminosalicylic acid or sulfonamides. Ester-type local anaesthetics such as procaine and cocaine that are hydrolysed by plasma cholinesterase may competitively enhance the neuromuscular blocking activity of suxamethonium; the amide local anaesthetic, lidocaine may have a similar effect.

There is an increased risk of myocardial depression when amide-type local anaesthetics such as bupivacaine, levobupivacaine, lidocaine, or ropivacaine are given with antiarrhythmics.

If local anaesthetics containing adrenaline are given for epidural or paracervical block during labour the use of an oxytocic drug post partum may lead to severe hypertension. Although there is no clinical evidence of dangerous interactions between adrenaline-containing local anaesthetics and MAOIs or tricyclic antidepressants, great care should nevertheless be taken to avoid inadvertent intravenous doses of the local anaesthetic preparation.

accidental intravascular injection

excessive or too rapid doses

absorption of large amounts through mucous membranes or damaged skin

absorption of large amounts from inflamed or highly vascular areas.