⚡ Quick Answer — What is Q-Siz SR 400?
Q-Siz SR 400 bevat quetiapine 400 mg (extended-release (once-daily)) from a WHO-GMP certified manufacturer (Healing Pharma) — an atypical antipsychotic with broad use across schizophrenia, bipolar disorder, and treatment-resistant depression. Mechanism: D2 + 5-HT2A antagonism plus prominent H1 antihistamine action (heavy sedation) plus alpha-1 blockade (orthostasis). Doses span a huge range by indication: 25–100 mg HS (off-label insomnia, anxiety adjunct — controversial), 300–800 mg/day (schizophrenia, bipolar mania), 150–300 mg/day (bipolar depression, MDD adjunct). Major class warnings: metabolic syndrome (weight, glucose, lipids — class effect), heavy sedation, orthostatic hypotension, QT prolongation, EPS (lower than first-generation antipsychotics), and FDA black box for elderly dementia mortality.
📦 Elke bestelling is gedekt door onze Reshipment Assurance Policy — als uw pakket niet binnen 20 werkdagen arriveert, sturen wij het opnieuw.
Waarom bestellen bij MedsBase
Onze generieke medicijnen zijn afkomstig van WHO-GMP gecertificeerde fabrikanten en worden wereldwijd verzonden in discrete, eenvoudige verpakkingen — geen medicijnnaam op de buitenkant van het pakket. Betalingen met kaart worden verwerkt via een gereguleerde processor (betalingsoverzichten vermelden een gereguleerde kaartbetalingprocessor — nooit “MedsBase” of een medicijnnaam). Crypto en SEPA bankoverschrijvingen worden ook geaccepteerd. Elke bestelling wordt ondersteund door ons Reshipment Assurance Policy.
What Is Q-Siz SR 400?
Q-Siz SR 400 is an oral extended-release (once-daily) tablet of quetiapine fumarate 400 mg manufactured by Healing Pharma. Quetiapine (US brand Seroquel IR / Seroquel XR) is an atypical (second-generation) antipsychotic launched by AstraZeneca in 1997. It is a D2 and 5-HT2A antagonist with strong H1 antihistamine and moderate alpha-1 antagonist activity. The H1 blockade drives the prominent sedation; the alpha-1 blockade drives orthostatic hypotension; the 5-HT2A antagonism reduces extrapyramidal side-effect risk compared with first-generation antipsychotics.
The XR (extended-release) formulation allows once-daily dosing and reduces peak plasma concentrations — less peak sedation immediately after the dose, but the overall daily AUC is similar to IR. XR cannot be split, crushed, or chewed.
Goedgekeurde indicaties
- Schizophrenia — acute and maintenance
- Bipolar mania — acute (monotherapy or with lithium / valproate)
- Bipolar depression — one of the few drugs FDA-approved for this; first-line in bipolar I depression
- Bipolar maintenance — with lithium or valproate
- Adjunctive treatment of MDD — XR formulation, 150–300 mg/day with an antidepressant
- Off-label: insomnia (low dose 25–50 mg), anxiety (controversial — metabolic risk for non-psychotic anxiety), agitation in dementia (used with caution given black-box warning)
Dosering per indicatie
| Indicatie | Start | Streefdosering | Maximum | Opmerkingen |
|---|---|---|---|---|
| Schizophrenia (XR) | 50 mg BID (or 300 mg HS XR) | 400–800 mg/day | 800 mg/day | Titrate over 4–7 days; XR allows once-daily HS dosing |
| Bipolar mania (acute) | 100 mg/day × day 1, increase by 100 mg/day | 400–800 mg/day | 800 mg/day | Rapid titration to control mania |
| Bipolar depression | 50 mg HS × day 1, then 100, 200, 300 | 300 mg/day at bedtime | 300 mg/day | Standard maximum for this indication |
| MDD adjunct (XR only) | 50 mg voor het slapen | 150–300 mg/day | 300 mg/day | Add to existing antidepressant; sedation often dose-limiting |
| Off-label insomnia | 25–50 mg HS | 25–50 mg HS | 100 mg HS | Controversial — metabolic risk for sleep dose makes this a poor first choice; reserve for patients who have failed multiple alternatives |
| Ouderen | 25–50 mg/day, slower titration | — | Consider 200–300 mg/day max | Greater sedation and orthostasis — falls risk |
Bijwerkingen
Side-effect profile by mechanism
| Werkingsmechanisme | Effecten | Notes / management |
|---|---|---|
| Metabolic (5-HT2C + H1 appetite drive) | Weight gain (often significant), increased blood glucose / new-onset diabetes, dyslipidaemia | Class warning — baseline weight, BP, fasting glucose, lipids; reassess at 3 months and annually |
| H1 blockade | Heavy sedation, drowsiness | Useful at bedtime; often limiting during the day. Less peak sedation with XR |
| Alpha-1 blockade | Orthostatische hypotensie, duizeligheid | Slow titration; check lying / standing BP |
| Anticholinergic (mild) | Dry mouth, constipation | Less than olanzapine |
| D2 blockade | Extrapyramidal symptoms (akathisia, parkinsonism, dystonia) | Lower than first-generation antipsychotics; akathisia at higher doses |
| Anders | QT-verlenging | Baseline ECG; caution with other QT-prolonging drugs |
| Zeldzaam | Tardive dyskinesia | Lower risk than typical antipsychotics but real with long-term use |
| Zeldzaam | Neuroleptic malignant syndrome | Hyperthermia, rigidity, autonomic instability — emergency |
| Zeldzaam | Hyperprolactinemie | Less than risperidone |
| Zeldzaam | Cataracts | Lens monitoring controversial; some clinicians order 6-monthly slit-lamp exam |
Geneesmiddelinteracties
CYP3A4 substrate: levels rise with strong inhibitors (ketoconazole, ritonavir, clarithromycin) — reduce dose. Levels fall with strong inducers (rifampin, phenytoin, carbamazepine) — loss of efficacy.
Additive sedation: alcohol, benzodiazepines, opioids, sedating antidepressants.
QT-verlenging: caution with citalopram (high dose), methadone, ondansetron, fluoroquinolones, ziprasidone.
Antihypertensiva: additive orthostasis with alpha-blockers, ACE inhibitors, diuretics.
Anticholinergic burden: additive with diphenhydramine, oxybutynin.
Metabolic Monitoring
All atypical antipsychotics carry a class warning for metabolic syndrome — weight gain, dyslipidaemia, and impaired glucose tolerance. Quetiapine sits in the higher-risk group (with olanzapine and clozapine). Standard monitoring: baseline + 3 months + annually: weight / BMI, waist circumference, fasting glucose or HbA1c, fasting lipid panel, blood pressure. Consider a switch to a lower-metabolic-risk agent (aripiprazole, lurasidone, ziprasidone) if weight / glucose deteriorates.
Veelgestelde vragen
How long does Q-Siz SR 400 take to work?
Acute psychosis or mania symptoms often respond within days; full benefit at 4–6 weeks. Bipolar depression response typically appears at 1–3 weeks at the 300 mg target.
Why is Q-Siz SR 400 used for sleep?
Quetiapine 25–50 mg HS produces heavy sedation through H1 blockade. Off-label sleep use has become widespread but is controversial — metabolic side effects accumulate even at low dose, and safer hypnotics exist.
Will Q-Siz SR 400 make me gain weight?
Likely yes — quetiapine is one of the more weight-gain-prone atypicals. Average weight gain at therapeutic doses is 4–7 kg over 12 months; some patients gain considerably more. Lifestyle interventions help; switching to aripiprazole or lurasidone may be needed if weight becomes problematic.
Is Q-Siz SR 400 safe in elderly patients with dementia?
FDA black-box warning for increased mortality in elderly with dementia-related psychosis or behavioural disturbance. Use only when behavioural and non-pharmacological strategies have failed and the symptoms are severe; lowest dose, shortest duration, with informed consent of family.
Can I drink alcohol on Q-Siz SR 400?
Avoid — additive sedation and orthostasis. Even moderate alcohol substantially increases sedation and falls risk.
What is the difference between IR and XR quetiapine?
IR peaks at 1–2 hours; XR peaks at ~6 hours and allows once-daily dosing. IR has more peak sedation just after the dose; XR has a smoother profile. Daily AUC is similar at equivalent doses.
Will Q-Siz SR 400 cause extrapyramidal side effects?
Quetiapine has the lowest EPS risk among atypicals along with clozapine. Akathisia at higher doses is the most common motor side effect; tardive dyskinesia risk exists with long-term use but is much lower than first-generation antipsychotics.
Is Q-Siz SR 400 safe in pregnancy?
Limited data — quetiapine is one of the better-studied atypicals in pregnancy. Continuation is reasonable when needed for serious mental illness; first-trimester exposure does not appear to increase major malformation rates above baseline.
Can I stop Q-Siz SR 400 abruptly?
Better to taper, especially after long-term use — abrupt discontinuation can produce withdrawal dyskinesia, insomnia, nausea, sweating, and rebound psychosis or mania. Reduce by 25–50 mg every 1–2 weeks.
How should Q-Siz SR 400 be stored?
Store at 15–30 °C in the original blister packaging, away from moisture and sunlight. Keep out of reach of children.
Gerelateerde alternatieven
Andere producten in Chronische aandoeningen die klanten ook bekijken:



























Beoordelingen
Er zijn nog geen beoordelingen