✓ Medically reviewed by · Last reviewed: May 2026
Pharmacy Researcher · 8 years experience
Pharmacy researcher with 8 years reviewing clinical drug information, generic formulation equivalence, and international pharmaceutical standards. Focuses on patient-facing accuracy in medication education.
Key Takeaways — Seroquel Generic (Quetiapine)
- Seroquel’s generic name is quetiapine fumarate. AstraZeneca’s patent expired in 2012 and generic quetiapine is now widely manufactured.
- Available in immediate-release (IR): 25 mg, 50 mg, 100 mg, 200 mg, 300 mg and extended-release (XR/SR): 50 mg, 150 mg, 200 mg, 300 mg, 400 mg.
- Approved for schizophrenia, bipolar I mania, bipolar depression, and major depressive disorder (adjunct).
- Widely used off-label for insomnia (25–50 mg) and anxiety disorders — one of the most common off-label psychiatry prescriptions globally.
- US retail price for Seroquel 300 mg × 30 can exceed $300 without insurance. Generic quetiapine at MedsBase starts from $18.
What Is the Generic Name for Seroquel?
Seroquel is a brand name manufactured by AstraZeneca. Its generic name is quetiapine fumarate. Seroquel was first approved by the FDA in 1997 for schizophrenia and quickly became one of the best-selling psychiatric drugs in the world. AstraZeneca’s patents expired in 2012, after which generic manufacturers began producing quetiapine fumarate at significantly lower prices.
Quetiapine is classified as an atypical antipsychotic (also called a second-generation antipsychotic). Unlike older antipsychotics, it has a broad receptor profile — blocking dopamine D2 receptors, serotonin 5-HT2A receptors, histamine H1 receptors, and adrenergic receptors — which accounts for both its therapeutic effects and its side effect profile.
Seroquel Generic Brand Names Available at MedsBase
The following quetiapine fumarate generics are available for worldwide delivery from MedsBase. All are manufactured at WHO-GMP certified facilities.
| Brand Name | Formulation | Strengths Available | Pack sizes | From |
|---|---|---|---|---|
| Seroquit | Immediate-release (IR) | 25 mg · 50 mg · 100 mg | 30, 60, 90, 180 tablets | $18 |
| Psyquit | Immediate-release (IR) | 25 mg · 100 mg · 200 mg · 300 mg | 30, 60, 90, 180 tablets | from $18 |
| Qutan SR 400 | Sustained-release (SR/XR) | 400 mg | 30, 60, 90, 180 tablets | $69 |
| Q-Siz SR 400 | Sustained-release (SR/XR) | 400 mg | 30, 60, 90, 180 tablets | $18 |
US pharmacy (brand Seroquel XR): $400–600
US pharmacy (generic quetiapine XR): $50–120
MedsBase (Q-Siz SR 400 or Qutan SR 400): from $18
Saving vs US generic: up to 90%
Immediate-Release (IR) vs Extended-Release (XR/SR) — Which to Choose?
Quetiapine comes in two formulations with different pharmacokinetic profiles and licensed indications:
| Feature | Immediate-Release (IR) | Extended/Sustained-Release (XR/SR) |
|---|---|---|
| Dosing | Twice daily (BID) for most indications | Once daily (OD), typically at bedtime |
| Peak plasma time | ~1.5 hours | ~6 hours |
| Schizophrenia | ✓ Licensed | ✓ Licensed |
| Bipolar mania | ✓ Licensed | ✓ Licensed |
| Major depression (adjunct) | Not typically used | ✓ Licensed (XR formulation specifically) |
| Off-label insomnia | 25–50 mg at bedtime (most common off-label use) | Less preferred for insomnia alone |
| Can be split? | Yes | No — XR/SR tablets must be swallowed whole |
Approved Uses of Quetiapine (Generic Seroquel)
Schizophrenia
Quetiapine is FDA-approved and widely used globally for both acute and maintenance treatment of schizophrenia. It reduces positive symptoms (hallucinations, delusions) and negative symptoms (social withdrawal, flat affect) through dopamine D2 and serotonin 5-HT2A blockade. Typical dose range: 150–750 mg/day in divided doses (IR) or as a single daily dose (XR).
Bipolar Disorder
Quetiapine has strong evidence in both phases of bipolar disorder. It is approved for:
- Bipolar mania (acute) — monotherapy or adjunct to mood stabilisers; dose 400–800 mg/day
- Bipolar depression — one of the few agents with regulatory approval for this phase; dose 300 mg/day (Seroquel XR formulation)
- Bipolar maintenance — reduces relapse frequency; long-term dose typically 400–800 mg/day
Major Depressive Disorder (Adjunct)
Quetiapine XR is approved as an adjunctive treatment for major depressive disorder (MDD) when an antidepressant alone is insufficient. Typical adjunct dose: 50–300 mg/day (XR formulation, bedtime). This indication is responsible for a large portion of quetiapine prescriptions — with many clinicians using it alongside SSRIs and SNRIs.
Off-Label Uses of Low-Dose Quetiapine
Low-dose quetiapine (typically 25–100 mg at bedtime) has become one of the most commonly prescribed off-label psychiatric treatments worldwide. The main off-label uses are:
- Insomnia — Quetiapine 25–50 mg at bedtime has significant sedative effects via H1 histamine blockade. It improves sleep onset and duration. Widely used for insomnia associated with psychiatric conditions, particularly anxiety and PTSD.
- Generalised anxiety disorder (GAD) — Evidence from RCTs supports quetiapine XR 150 mg/day for GAD. Some guidelines include it as a second-line option.
- PTSD — Quetiapine is one of the most commonly used adjunct agents in PTSD, particularly for nightmares and hyperarousal. Evidence is moderate but real-world use is extensive.
- Agitation in dementia — Used at low doses in carefully selected patients when non-pharmacological approaches fail.
Dosing Overview
| Condition | Starting dose | Usual target | Formulation |
|---|---|---|---|
| Schizophrenia | 25–50 mg BID | 150–750 mg/day | IR or XR |
| Bipolar mania | 50 mg BID | 400–800 mg/day | IR or XR |
| Bipolar depression | 50 mg OD (PM) | 300 mg OD (PM) | XR preferred |
| MDD adjunct | 50 mg OD (PM) | 150–300 mg OD | XR |
| Insomnia (off-label) | 25 mg at bedtime | 25–100 mg at bedtime | IR |
Side Effects
Quetiapine’s broad receptor profile creates a predictable side effect profile. Common effects:
- Sedation / drowsiness — very common; mediated by H1 blockade. This is why low doses are used for insomnia.
- Weight gain — moderate; less than olanzapine or clozapine but significant over time. Monitor BMI.
- Dry mouth, constipation — anticholinergic effects, more common at higher doses
- Postural hypotension — dizziness on standing, especially at initiation; rise slowly
- QTc prolongation — clinically relevant at high doses or in combination with other QT-prolonging drugs
- Metabolic effects — glucose dysregulation; monitor blood glucose in long-term use
- Extrapyramidal side effects (EPS) — less frequent than typical antipsychotics but can occur at high doses
Seroquel Generic Price Comparison
| Strength & form | US pharmacy (GoodRx estimate) | MedsBase price | Saving |
|---|---|---|---|
| Quetiapine 25 mg × 30 | $15–40 | $18 | Similar (small pack) |
| Quetiapine 100 mg × 30 | $15–60 | $18 | Up to 70% |
| Quetiapine 300 mg × 30 | $40–120 | from $18 | Up to 85% |
| Quetiapine XR 400 mg × 30 | $50–120 | $18 (Q-Siz SR 400) | Up to 90% |
🛡️ Every MedsBase order includes Reshipment Assurance — if your parcel doesn’t arrive, we reship at no extra cost.
Frequently Asked Questions
What is the generic name for Seroquel?
The generic name for Seroquel is quetiapine fumarate. Seroquel was the original brand name from AstraZeneca. After the patent expired in 2012, generic manufacturers began producing quetiapine fumarate tablets in the same strengths as branded Seroquel. Generic brand names include Seroquit, Psyquit, Qutan SR, and Q-Siz SR.
Is generic quetiapine as effective as Seroquel?
Yes. Generic quetiapine fumarate must meet the same bioequivalence standards as the branded product — the FDA and EMA require that the generic delivers the same amount of drug at the same rate as the original. Independent comparative studies have not found clinically meaningful differences between generic and branded quetiapine in psychiatric outcomes.
What is Seroquel 25 mg used for?
Quetiapine 25 mg is the lowest available strength and is most commonly used for off-label indications including insomnia (25–50 mg at bedtime) and anxiety. It is also used as a starting dose during titration for schizophrenia or bipolar disorder, particularly in elderly patients or those sensitive to sedation. At 25 mg, the predominant effect is histamine H1 blockade (sedation) rather than dopamine blockade.
Can quetiapine be used for sleep?
Low-dose quetiapine (25–50 mg) is widely prescribed off-label for insomnia, particularly in patients with comorbid psychiatric conditions like anxiety, PTSD, or depression. The sedative effect is primarily driven by H1 antihistamine activity. This is not an FDA-approved indication, but it is a common and well-documented clinical practice. Evidence from clinical trials supports modest improvements in sleep onset and total sleep time.
What is the difference between Seroquel and Seroquel XR?
Seroquel (immediate-release, IR) reaches peak plasma levels in about 1.5 hours and is typically dosed twice daily. Seroquel XR (extended-release, also called SR or sustained-release) releases the drug over several hours, reaching peak levels in about 6 hours and dosed once daily — usually at bedtime. The XR formulation has regulatory approval specifically for major depressive disorder adjunct therapy and may be better tolerated in some patients due to smoother plasma levels.
How long does quetiapine take to work for sleep?
When used for insomnia, quetiapine’s sedative effects typically begin within 30–60 minutes of taking the dose. Most people report improved sleep onset within the first night at 25–50 mg. For psychiatric indications (schizophrenia, bipolar), the full antipsychotic effect develops over 2–6 weeks as the drug reaches steady state and neuroadaptation occurs.
What happens if I stop taking quetiapine suddenly?
Abrupt discontinuation of quetiapine after prolonged use can cause withdrawal-like symptoms including rebound insomnia, nausea, vomiting, and anxiety. This is particularly pronounced at higher doses or after long-term use. The recommended approach is a gradual taper — reducing the dose by 25–50 mg every 1–2 weeks under clinical supervision. Never stop without discussing the plan with your prescriber.
What is the maximum dose of quetiapine?
The maximum licensed dose is 800 mg/day for schizophrenia and bipolar mania. For bipolar depression and MDD adjunct, the maximum is 300 mg/day. In clinical practice, doses above 800 mg/day are rarely used. Higher doses significantly increase the risk of QTc prolongation and metabolic side effects.
Can quetiapine cause weight gain?
Yes. Weight gain is a documented side effect of quetiapine, mediated through H1 antihistamine blockade and metabolic effects. The degree of weight gain is generally less than olanzapine or clozapine but more than aripiprazole or ziprasidone. In long-term use, metabolic monitoring (weight, glucose, lipids) is recommended. Low-dose quetiapine (25–50 mg) for insomnia carries a lower metabolic risk than full therapeutic doses.
Is quetiapine addictive?
Quetiapine is not classified as a controlled substance and does not produce the euphoria or craving associated with drugs of abuse. However, physical dependence can develop with long-term use — meaning that abrupt discontinuation causes withdrawal symptoms. Psychological dependence on its sedative effects for sleep has been reported. It should be discontinued with a supervised taper rather than stopped suddenly.
Who manufactures the generic quetiapine sold at MedsBase?
MedsBase stocks quetiapine products manufactured by established Indian pharmaceutical companies operating under WHO-GMP certification — the same quality standard used for international pharmaceutical supply chains. Seroquit and Psyquit are immediate-release quetiapine at strengths from 25–300 mg; Qutan SR 400 and Q-Siz SR 400 are extended-release 400 mg tablets for once-daily dosing.
Related guides: Best Antidepressants in 2026 · Bipolar Disorder Guide · Depression Guide
Written by
Sophie ChenPharmaceutical Content Researcher · 8 years experience
Sophie Chen is a pharmaceutical content researcher with 8 years covering generic medication access and clinical pharmacology. She specialises in international regulatory frameworks, bioequivalence standards, and patient-facing education on therapeutic drug classes. She is not a clinician.