A Look At Pharmacological Treatment Of Tourette Syndrome

Tourette's syndrome is a group of extrapyramidal diseases that occur in adolescence and are characterized by sudden involuntary multiple twitches of the muscles of the head, limbs, and trunk, accompanied by explosive guttural sounds or swearing words. Typical manifestations are multiple tics, involuntary vocalization, speech and behavior disorders; may be accompanied by obsessions, personality disorders, and attention deficit hyperactivity disorder. Generally, patients with mild symptoms do not need treatment, and pharmacological treatment of tourette syndrome should be used early for those who have been diagnosed. The principle of treatment is: start treatment with a small dose, slowly increase the dose, and reduce side effects. Because pharmacological treatment of tourette syndrome is symptomatic, maintenance therapy should be performed for a certain period of time. The duration of maintenance therapy will depend on the specific circumstances of each patient. Common drugs are:

(1) Haloperidol: It is a selective central dopamine receptor blocker. In 1961, Seignot reported that haloperidol was successfully used in the treatment of tics. After that, many reports confirmed that the drug is indeed effective. It is now widely used in Tourette's syndrome and is the first choice drug, with a curative effect of 60% to 90%. It is mainly effective for motor and vocal tics, which can make many patients with Tourette's syndrome return to normal, but it has little effect on some accompanying symptoms of Tourette's syndrome. About half of the patients could not tolerate its adverse reactions, such as bad mood, lethargy, extrapyramidal symptoms, cognitive retardation affecting learning, heart block, etc., bradykinesia and akathisia are the main adverse reactions of haloperidol treatment . Trihexyphenidyl should be used concomitantly to reduce extrapyramidal reactions.

(2) Pimozide: The efficacy is similar to that of haloperidol, but it has no sedative effect and is easily accepted by patients. Now it has been widely used as a second-line drug. The drug has a long action time, and the single oral time is 24 hours, so it is enough to take it once a day. Heart block caused by Pimozide is more common than haloperidol, which can cause T wave inversion, U wave appearance, Q-T interval prolongation, bradycardia, etc. Therefore, before and during treatment, every 1 to 2 months An electrocardiogram should be performed, and the drug should be discontinued once T wave inversion or u wave appears. Long-term use can cause anxiety.

(3) α2-adrenergic receptor blocker clonidine hydrochloride: The mechanism of action of this product as a pharmacological treatment of tourette syndrome may be to inhibit the release of synaptic norepinephrine in the locus coeruleus, thereby reducing tic symptoms. Clonidine is a safe and effective anti-tic drug with an effective rate of 22% to 70%. The onset time is slower than that of haloperidol, and it takes 3 weeks or more to be effective. In addition, clonidine may be the first choice for the treatment of attention deficit and hyperactivity. The adverse reactions of clonidine include drowsiness, dry mouth, headache, dizziness, irritability, increased heart rate and decreased blood pressure. Blood pressure and pulse should be monitored during treatment, and electrocardiogram should be performed regularly. Once adverse reactions occur, the dose should be adjusted and the rate of drug addition should be slowed down. Do not stop the drug suddenly during the treatment process, otherwise an acute drug withdrawal reaction may occur.

(4) Inosine: Some people think that inosine treatment may be effective, because inosine is an intermediate product of purine metabolism, which can quickly enter the central nervous tissue through the blood-cerebrospinal fluid barrier, and has sedative and anticonvulsant effects, which can increase the release of dopamine, It cannot be excluded that inosine acts on dopaminergic axon terminals and acts as a dopamine receptor antagonist similar to haloperidol. There are reports in China that the combined treatment of inosine and haloperidol is more effective, and can reduce the dosage of haloperidol and reduce adverse reactions.

Regarding the combination pharmacological treatment of tourette syndrome, it is mostly used in the following situations: First, the patient's symptoms cannot be controlled with haloperidol monotherapy or the adverse reactions are too large to continue the treatment; second, the patient's movement and vocal symptoms still exist after clonidine is used. Commonly used in combination with haloperidol and clonidine, the advantage is that both are in very small doses, and satisfactory results can be achieved with fewer adverse reactions. Haloperidol and Tipride can also be used in combination.

In addition to the pharmacological treatment of tourette syndrome, there are also psychological treatment and surgical treatment, all of which have their own characteristics and effects. Patients should choose the most suitable treatment method according to their own situation.