Drug search by name

Seroquel and Thioridazine

Determining the interaction of Seroquel and Thioridazine and the possibility of their joint administration.

Check result:

Seroquel <> Thioridazine

Relevance: 13.08.2023 Reviewer: Shkutko P.M., M.D., in

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Consumer:

Using thioridazine together with QUEtiapine is not recommended. Combining these medications can increase the risk of an irregular heart rhythm that may be serious. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, or fast or pounding heartbeats during treatment with either of these medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Professional:

CONTRAINDICATED: Thioridazine can cause dose-related prolongation of the QT interval. Theoretically, coadministration with other agents that can prolong the QT interval including other antipsychotic agents may result in additive effects and increased risk of ventricular arrhythmias. Thioridazine treatment alone has been associated with several reported cases of torsade de pointes and sudden death.

Coadministration with thioridazine may decrease the plasma concentrations of quetiapine. The mechanism of interaction is unknown. In one study, thioridazine (200 mg twice a day for 8.5 days) administered to patients stabilized on quetiapine (300 mg twice a day) resulted in decreases in mean quetiapine peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) by 47%, 40% and 31%, respectively. Quetiapine oral clearance (Cl/F) increased by 68%. Patients in the study reported increases in dizziness, insomnia, and dry mouth during coadministration, while sedation and prolonged sleep duration became worse in more than 25% of the patients. This is consistent with additive anticholinergic and CNS-depressant effects of these agents. Excessive anticholinergic effects can also result in paralytic ileus, hyperthermia, heat stroke, and the anticholinergic intoxication syndrome. Peripheral symptoms of anticholinergic intoxication commonly include mydriasis, blurred vision, flushed face, fever, dry skin and mucous membranes, tachycardia, urinary retention, and constipation. Central symptoms may include memory loss, disorientation, incoherence, hallucinations, psychosis, delirium, hyperactivity, twitching or jerking movements, stereotypy, and seizures. Other adverse effects that may be increased with this combination include orthostatic hypotension, extrapyramidal symptoms, and tardive dyskinesia.

MANAGEMENT: The concurrent use of thioridazine with other medications that can prolong the QT interval is considered contraindicated.

References

Johnson AL, Hollister LE, Berger PA "The anticholinergic intoxication syndrome: diagnosis and treatment." J Clin Psychiatry 42 (1981): 313-7
"Product Information. Seroquel (quetiapine)." Zeneca Pharmaceuticals, Wilmington, DE.
Stadnyk AN, Glezos JD "Drug-induced heat stroke." Can Med Assoc J 128 (1983): 957-9
Potkin SG, Thyrum PT, Alva G, Bera R, Yeh C, Arvanitis LA "The safety and pharmacokinetics of quetiapine when coadministered with haloperidol, risperidone, or thioridazine." J Clin Psychopharmacol 22 (2002): 121-30
Mann SC, Boger WP "Psychotropic drugs, summer heat and humidity, and hyperplexia: a danger restated." Am J Psychiatry 135 (1978): 1097-100
Warnes H, Lehmann HE, Ban TA "Adynamic ileus during psychoactive medication: a report of three fatal and five severe cases." Can Med Assoc J 96 (1967): 1112-3
Lee BS "Possibility of hyperpyrexia with antipsychotic and anticholinergic drugs." J Clin Psychiatry 47 (1986): 571
"Quetiapine for schizophrenia." Med Lett Drugs Ther 39 (1997): 117-8
Sarnquist F, Larson CP Jr "Drug-induced heat stroke." Anesthesiology 39 (1973): 348-50
Moreau A, Jones BD, Banno V "Chronic central anticholinergic toxicity in manic depressive illness mimicking dementia." Can J Psychiatry 31 (1986): 339-41

Seroquel

Generic Name: quetiapine

Brand name: Seroquel, Seroquel XR

Synonyms: n.a.

What is Seroquel?

Thioridazine

Generic Name: thioridazine

Brand name: Mellaril, Mellaril-S

Synonyms: n.a.

What is Thioridazine?

+ Add a drug Remove all

In the course of checking the drug compatibility and interactions, data from the following reference sources was used: Drugs.com, Rxlist.com, Webmd.com, Medscape.com.

The list of popular interactions