Hypokalemic sensory overstimulation is characterized by a subjective experience of sensory overload and a relative resistance to

lidocaine Lidocaine, also known as lignocaine and sold under the brand name Xylocaine among others, is a local anesthetic of the amino amide type. It is also used to treat ventricular tachycardia. When used for local anaesthesia or in nerve blocks, lidoca ...

local anesthesia. The sensory overload is treatable with oral potassium gluconate. Individuals with this condition are sometimes diagnosed as having attention deficit hyperactivity disorder (

ADHD Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by excessive amounts of inattention, hyperactivity, and impulsivity that are pervasive, impairing in multiple contexts, and otherwise age-inapp ...

), raising the possibility that a subtype of ADHD has a cause that can be understood mechanistically and treated in a novel way. It is not to be confused with

hot tooth syndrome Pulpitis is inflammation of dental pulp tissue. The pulp contains the blood vessels, the nerves, and connective tissue inside a tooth and provides the tooth’s blood and nutrients. Pulpitis is mainly caused by bacterial infection which itself is ...

Signs and symptoms

Cause

Hypokalemic sensory overstimulation is a term coined by MM Segal and colleagues to describe a syndrome of sensory overstimulation, ineffectiveness of the local anesthetic lidocaine, and in females, premenstrual syndrome. This initial report was followed by discussion in a second article of tens of families with apparent autosomal dominant inheritance of this condition. The similarities were described clinically to ADHD and mechanistically and therapeutically to disorders of ion channels, in particular to the muscle disorder

hypokalemic periodic paralysis Hypokalemic periodic paralysis (hypoKPP), also known as familial hypokalemic periodic paralysis (FHPP), is a rare, autosomal dominant channelopathy characterized by muscle weakness or paralysis when there is a fall in potassium levels in the blood ...

. Some females with

premenstrual syndrome Premenstrual syndrome (PMS) refers to emotional and physical symptoms that regularly occur in the one to two weeks before the start of each menstrual period. Symptoms resolve around the time menstrual bleeding begins. Different women experienc ...

may have the same autosomal dominant disorder underlying their symptoms.

Diagnosis

A test for lidocaine ineffectiveness was briefly described in the 2014 paper but the controlled trial has not yet been completed.

Treatment

The use of oral potassium and avoiding high carbohydrate meals can help treat it according to recent tests, following the same approach that is standard for the muscle disease

. Since this condition includes ineffectiveness of the sodium-channel blocker

, the amide-type local anesthetic used in dental care

articaine Articaine is a dental amide-type local anesthetic. It is the most widely used local anesthetic in a number of European countriesOertel R, Ebert U, Rahn R, Kirch W. Clinical pharmacokinetics of articaine. Clin Pharmacokinet. 1997 Dec;33(6):418. an ...

was tested and found to be effective in one member of the family. No data about other local anesthetics effective in these individuals for non-dental procedures has yet been published.

References

{{Anesthesia Pain Neurological disorders Dentistry Anesthesia Attention deficit hyperactivity disorder Local anesthetics Sodium channel blockers