Risperidone vs. Seroquel

Introduction

Schizophrenia affects 1.5% of adults in the US (or about 4.6 million people), requiring the use of antipsychotic drugs such as Risperidone and Seroquel. Some of the most common symptoms of schizophrenia include delusions, hallucinations, and disorganized thinking, among others.

The exact cause of schizophrenia is unknown, but researchers believe that a combination of genetic, psychological, and environmental factors can make a person more likely to develop the condition. Some cases of schizophrenia are triggered by a traumatic event.

Most antipsychotic drugs work by blocking dopamine receptors in the brain which regulates the flow of messages, which can reduce a patient’s psychotic symptoms. Let’s take a look at the two most common drugs used to treat schizophrenia: Risperidone and Seroquel.

About Risperidone and Seroquel

What is Risperidone?

Risperidone belongs to a class of atypical antipsychotic medications. It works by regulating the activity of certain neurotransmitters within the brain, which may be able to alleviate symptoms of schizophrenia, such as hallucinations, disorganized thinking, and delusions. Risperidone is an antagonist for serotonin and dopamine receptors with high affinity.

The drug is available in various forms, including liquid solutions, injectables, and tablets at different dosage levels.

Dosing depends on various factors, such as the patient's medical conditions, age, and lifestyle. It is worth mentioning that Risperidone doesn't cure schizophrenia but plays an important role in keeping the patient's symptoms in check. The first effects of treatment with Risperidone can take several weeks or even months. However, patients may be able to notice treatment as early as 24 hours.

What conditions is Risperidone approved to treat?

Although Risperidone is primarily used to manage the symptoms of schizophrenia, it has been shown to help with other conditions such as bipolar disorder, acute mania, and irritability associated with autistic disorder. It is worth mentioning that this medicine should not be used to treat behavioral issues in older patients with dementia. Risperidone Is only available with a doctor’s prescription.

How does Risperidone work for Schizophrenia?

Researchers haven’t fully understood the mechanism of action for Risperidone. However, it is known that the drug works by regulating dopamine and serotonin receipts in the brain. Specifically, Risperidone is an antagonist for dopamine and serotonin receptors with very high affinity and has been shown to modulate endogenous dopamine release.

The improvement in patient symptoms is thought to be accomplished by the blockage of D2 receptors in the mesolimbic pathway. Additionally, Risperidone has been shown to have a high affinity for alpha 1- and alpha 2- receptors and histamine H1 receptors. This may have therapeutic effects on the patient.

Treating schizophrenia requires you to take Risperidone for a long period of time. It is not recommended to discontinue taking Risperidone even if you feel better. Missing too many doses of Risperidone could increase your risk for a relapse.

Note that patients have a risk of overdosing on Risperidone which can lead to fatigue, uncontrolled muscle spasms, seizures, and rapid heart rate. Studies have found that a toxic dose in rats is about 57.7 mg/kg when taken orally and 34 mg/kg when administered intravenously.

What is Seroquel?

Seroquel belongs to a class of atypical antipsychotic medications that are used to treat schizophrenia, major depressive disorder, and bipolar disorder, among others. Although Seroquel is useful in treating schizophrenia, it does have a few side effects that can be serious. The most common side effects include feeling faint, gaining weight, and being drowsy.

The more serious side effects of Seroquel include neuroleptic malignant syndrome, tardive dyskinesia, and a much higher risk of stroke in older patients who have previously had dementia-related psychosis. For these reasons, it is extremely important to talk to a medical doctor before starting treatment with Seroquel.

What conditions is Seroquel approved to treat?

Seroquel has been approved by the FDA to treat schizophrenia. It is also being used to manage symptoms of bipolar disorder, repeated episodes of anxiety, and major depressive disorder.

How does Seroquel work for Schizophrenia?

Seroquel can help treat schizophrenia by affecting various chemicals in the brain, such as serotonin and dopamine. Having too much dopamine in the brain can cause a person to hallucinate (see things that are not there) or have delusional thoughts. Excessive dopamine levels can also disrupt muscle movements.

Seroquel works by regulating the neurotransmitters in the brain and restoring the balance between them. This decreases hallucinations and improves the patient's concentration levels. The precise mechanism of action for Seroquel is not known. However, like most antipsychotic drugs, Seroquel is believed to reduce dopaminergic neurotransmission in the mesolimbic pathway.

It has a strong affinity for D2, alpha 1, 5-HT1A, H1, and 5-HT2a receptors. Studies have shown a relationship between D2 receptor occupancy and antipsychotic effects. Seroquel has been shown to occupy many D2 receptors when used appropriately.

A key property of Seroquel is that it has antagonist actions at 5-HT2A receptors, allowing it to maintain a high 5-HT2A/D2 ratio, which makes it effective as an antipsychotic drug. More notably, Seroquel has a higher affinity for 5-HT2A than for D2 receptors.

Effectiveness

How effective are Risperidone and Seroquel for treating Schizophrenia?

Studies have shown that Risperidone is very effective at managing the symptoms of schizophrenia in both the short and long term. However, there is a large interindividual variability in response to the drug. Clinical trials with placebo-controlled comparators have shown that Seroquel is very effective at reducing the symptoms of schizophrenia.

Neither drug will work right away. It can take several days, weeks, and even months for Risperidone and Seroquel to improve the symptoms of schizophrenia. Moreover, finding the right dosage is a trial-and-error process.

Although one study found no significant difference between Risperidone and Seroquel for treating active psychotic signs (due to schizophrenia), it was observed that Risperidone was superior to Seroquel in decreasing the PANSS general psychopathology sub-scores and total scores.

The starting dose for Seroquel is about 25 mg in children and teenagers. Meanwhile, the typical starting dose of Risperidone is about 0.5 mg per day in the morning or evening. The dosage may increase slowly as your doctor makes important observations over the course of 24 hours.

Dosage information

How is Risperidone administered for Schizophrenia?

The standard dose for Risperidone is 0.5 mg per day.

Side Effects

What are the most-common side effects of Risperidone?

Here are the most common side effects of Risperidone:

Dizziness
Lightheadedness
Nausea
Weight gain
Fatigue
Drowsiness
Risk of falling
Weight gain

Are there any potential serious side effects of Risperidone?

* If you experience any of these serious side effects, seek medical help immediately

Abrupt changes to the mood
Difficulty swallowing
Shaking and tremors
Interrupted breathing while sleeping
Muscle spasms
Increased thirst
Increased urination
High blood sugar
Higher triglyceride levels
Higher risk of developing heart disease
Tardive dyskinesia
Increase in prolactin
Decreased sexual ability
Enlarged breasts in men
Inability to produce semen
Seizures
Neuroleptic malignant syndrome

What are the most-common side effects of Seroquel?

Here are the most common side effects of Seroquel:

Feeling dizzy
Headaches
Changes to weight
Changes to appetite
Constipation
Enlarged breasts in men
Pain in breasts
Leaking breast milk in women
Irregular periods or no periods in women
Fast heartbeats
Feeling of fatigue
Problems with movement

Are there any potential serious side effects of Seroquel?

* If you experience any of these serious side effects, seek medical help immediately

Twitching
Jerking movements
Inability to control the face, tongue, or other parts of the body
Infections of the ear, bladder, chest, and eye
Symptoms of flu
High temperature
Swelling in the leg (a sign of blood clots)

Contraindications and interactions

Warnings and general precautions for Risperidone and Seroquel

Risperidone has a black box warning in elderly patients who are at a higher risk of death. Furthermore, this drug is contraindicated in patients with a known hypersensitivity to Risperidone

Seroquel has a black box warning in elderly patients with dementia-related psychosis.

Contraindications and important interactions for Risperidone and Seroquel

Contraindications

Risperidone

The following conditions are contraindicated with Risperidone:

High prolactin level
Drug abuse
Overweight
Dehydration
Too much fat in the blood
Diabetes
Breast cancer
Neutrophils
Parkinsonism
Heart attack
Chronic heart failure
Stroke
Hardening of the arteries
Liver problems

Check with your doctor before taking this drug.

Seroquel

Furthermore, this drug is contraindicated in patients with the following conditions:

Low thyroid levels
High prolactin level
Dehydration
Overweight
Anemia
Low amount of potassium in the blood
Diabetes
Low levels of white blood cells
Confusion
Closed-angle glaucoma
Heart attack
Inflammation
Liver problems
Seizures
Enlarged prostate
Dementia in elderly patients

Check with your doctor before taking this drug.

Drug/Medication Interactions

Risperidone

Bepridil
Bromopride
Cisapride
Dronedarone
Levoketoconazole
Levomethadyl
Mesoridazine
Metoclopramide
Pimozide
Piperaquine
Saquinavir
Sparfloxacin
Terfenadine
Thioridazine
Ziprasidone
Acecainide
Adagrasib
Ajmaline
Amiodarone
Amisulpride
Amitriptyline
Anagrelide
Apomorphine
Aprindine
Aripiprazole
Aripiprazole Lauroxil
Arsenic Trioxide
Asenapine
Astemizole
Azimilide
Azithromycin
Bretylium
Buprenorphine
Bupropion
Buserelin
Disopyramide
Dofetilide
Dolasetron
Domperidone
Donepezil
Doxepin
Droperidol
Efavirenz
Encainide
Encorafenib
Enflurane
Entrectinib
Erythromycin
Escitalopram
Fedratinib
Fexinidazole
Fingolimod
Flecainide
Fluconazole
Fluoxetine
Formoterol
Foscarnet
Fostemsavir
Gemifloxacin
Ginkgo Biloba
Glasdegib
Gonadorelin
Goserelin
Halofantrine
Haloperidol
Histrelin
Hydroquinidine
Hydroxychloroquine
Ceritinib
Chloral Hydrate
Chloroquine
Chlorpromazine
Citalopram
Clarithromycin
Clofazimine
Clothiapine
Clozapine
Crizotinib
Dabrafenib
Dasatinib
Degarelix
Delamanid
Desipramine
Deslorelin
Deutetrabenazine
Dexmedetomidine
Dexmethylphenidate
Dibenzepin

Seroquel

Amiodarone
Moxifloxacin
Quinidine
Sotalol
Thioridazine
Procainamide
Phenytoin
Itraconazole
Ketoconazole
Cetirizine
Diphenhydramine
Carisoprodol
Cyclobenzaprine
Codeine
Hydrocodone

Food/Beverage/Supplement Interactions

Risperidone

Check-in with your doctor or pharmacist.

Beverages to avoid with Risperidone:

Alcohol
Tea
Cola

Supplements to avoid with Risperidone:

Vitamin D

Seroquel

Foods to avoid with Seroquel:

Grapefruit

Beverages to avoid with Seroquel:

Grapefruit juice

Supplements to avoid with Risperidone:

Avoid supplements that make you feel sleepy

Cost Comparison

How much do Risperidone and Seroquel cost?

Both Risperidone and Seroquel are moderately priced at $70 or more for a supply of 30 tablets. Generic versions of Risperidone and Seroquel are covered by the majority of Medicare And insurance plans. You can also secure lower prices by going to certain pharmacies and using coupon codes.

Popularity of Risperidone and Seroquel

Both Risperidone and Seroquel are extremely popular in the US. Risperidone had 4.5 million prescriptions in 2020, costing about $11 per prescription. Meanwhile, Seroquel had 10.6 million prescriptions costing about $22.4 per prescription. This makes Seroquel the more popular of the two medications.

Conclusion

Takeaway

So there you have it, a detailed comparison of Risperidone and Seroquel. Affordability for either drug depends on your insurance plan, which pharmacy you go to, and the total supply you plan on buying.

Both drugs are fairly effective at treating schizophrenia; however, you should be extremely careful when changing dosing. Always report any adverse side effects to your doctor right away.