Quesara contains quetiapine, an atypical antipsychotic, in strengths including 25 mg. It treats schizophrenia and bipolar disorder, and is used as add-on treatment in depression. At 25 mg it is often being used for sedation rather than as an antipsychotic, which is worth understanding.
What is Quesara?
Quesara contains quetiapine, an atypical (second-generation) antipsychotic, available in a range of strengths from 25 mg upward. It is a Schedule 5 medicine, and the same ingredient is sold as Dopaquel, Seroquel and Quetin.
Quetiapine blocks dopamine D2 and serotonin 5-HT2A receptors, and also acts on histamine and adrenergic receptors. Excess dopamine signalling in certain brain pathways is associated with psychotic symptoms — hallucinations, delusions, disordered thinking — and blocking it reduces them.
The added serotonin action is what makes the atypical antipsychotics different from older ones: it substantially reduces the movement-related side effects that made first-generation antipsychotics so hard to tolerate.
The amount matters enormously with quetiapine, more than with most medicines. It behaves almost like different drugs at different strengths:
| Amount | What predominates |
|---|---|
| 25–50 mg | Antihistamine effect — sedation, sleep |
| 50–300 mg | Mood effects; add-on in depression, anxiety |
| 300–800 mg | Antipsychotic effect for schizophrenia, mania |
At 25 mg, quetiapine is essentially working as a sedative, not as an antipsychotic — the dopamine blockade at that level is minimal. That is why someone on 25 mg and someone on 600 mg are being treated for very different things.
What is Quesara commonly used for?
- Schizophrenia, at higher amounts, for acute episodes and maintenance.
- Bipolar disorder — manic episodes, bipolar depression and long-term mood stabilisation.
- Major depression, as add-on treatment where an antidepressant alone has not been enough.
- Generalised anxiety disorder, in some circumstances.
- Agitation in other conditions, under specialist care.
- Insomnia, at low amounts — a very common use, and one worth questioning.
About low-dose quetiapine for sleep
Prescribing 25 mg quetiapine as a sleeping aid is widespread, and it does work — the antihistamine effect is strongly sedating. But it deserves a conversation rather than acceptance:
The evidence for it in insomnia is weak. It is not a licensed use, and guidelines do not recommend it as a routine sleep treatment.
The metabolic risks apply even at low amounts. Weight gain, raised blood sugar and raised cholesterol are quetiapine’s principal long-term burdens, and they do not disappear at 25 mg.
Better options usually exist. Cognitive behavioural therapy for insomnia (CBT-I) has the strongest evidence of anything for chronic insomnia, and its benefits persist after treatment ends. Addressing an underlying cause — anxiety, depression, pain, sleep apnoea, alcohol — often resolves the sleep problem entirely.
If you have been given Quesara only for sleep, it is entirely reasonable to ask your doctor whether it is still the right choice and what else might be tried. If it is part of treatment for schizophrenia, bipolar disorder or depression, that is a different situation — see below.
How Quesara fits into this medicine category
| Group | Examples | Role |
|---|---|---|
| Atypical antipsychotics | Quetiapine (Quesara, Dopaquel), risperidone, olanzapine | Schizophrenia, bipolar disorder, add-on in depression |
| First-generation antipsychotics | Haloperidol, chlorpromazine | Psychosis; more movement side effects |
| Mood stabilisers | Lithium, valproate, lamotrigine | Bipolar disorder |
| Antidepressants | SSRIs, amitriptyline | Depression and anxiety |
| Benzodiazepines | Clobazam (Urbanol) | Short-term anxiety; seizures |
See the mental health and neurology medicines hub.
What to check before using Quesara
Take it in the evening because of the sedation, and check whether yours is immediate-release or extended-release — they are taken differently and are not interchangeable. Extended-release tablets must be swallowed whole.
Do not drive until you know how it affects you.
Do not drink alcohol with it.
Tell your prescriber or pharmacist if you:
- Have diabetes, or a family history of it.
- Have heart disease, a rhythm problem or a long QT interval.
- Have low blood pressure or faint on standing.
- Have liver disease, epilepsy, cataracts, or a history of low white blood cell counts.
- Have Parkinson’s disease or dementia. Antipsychotics carry increased risks in elderly people with dementia.
- Are pregnant, planning pregnancy or breastfeeding.
- Are older, where sedation, falls and low blood pressure are more likely.
- Take other sedating medicines, an antidepressant, a medicine affecting heart rhythm, or ketoconazole, erythromycin, phenytoin or carbamazepine.
Expect metabolic monitoring — weight, blood pressure, blood sugar and cholesterol before starting and periodically after — even at low amounts.
Follow the dispensing label exactly. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
Do not stop abruptly. Stopping suddenly causes withdrawal — nausea, vomiting, insomnia, agitation — and, if you take it for schizophrenia or bipolar disorder, risks a rapid relapse. Any change is tapered under medical supervision.
Never stop because you feel well if you take it for a psychiatric condition. Feeling well is the medicine working, and stopping is the commonest route back to hospital.
Weight gain and metabolic effects are the main long-term concern and are worth raising early rather than accepting silently — there are options, including a switch to an antipsychotic with a lower metabolic burden.
Sedation is often heavy at first and usually eases over weeks.
Dizziness on standing is common early; rise slowly.
Movement side effects are less likely than with older antipsychotics but possible — tremor, stiffness, restlessness, or involuntary movements of the face or tongue. Report these.
Neuroleptic malignant syndrome is rare but an emergency: high fever, severe muscle stiffness, confusion, sweating and a racing pulse require immediate care.
Seek urgent medical attention for high fever with muscle stiffness and confusion; a seizure; palpitations, fainting or an irregular heartbeat; uncontrolled movements of the face or tongue; marked thirst, frequent urination and unexplained weight loss; a persistent sore throat with fever; or thoughts of self-harm.
Related medicine guides
Frequently asked questions
What is Quesara 25 mg used for? At 25 mg, quetiapine is usually being used for its sedating effect — often for sleep or anxiety — rather than as an antipsychotic, which requires much higher amounts.
Is it the same as Seroquel? The active ingredient is the same — quetiapine. The brand differs.
I was given it just for sleep. Is that appropriate? It is widely done and it works, but the evidence in insomnia is weak and the metabolic risks apply even at low amounts. Worth asking your doctor about alternatives such as CBT for insomnia.
Will it make me gain weight? Weight gain and effects on blood sugar and cholesterol are common, including at lower amounts. Monitoring is done for this reason.
Can I stop taking it when I feel better? Not on your own. Stopping abruptly causes withdrawal, and in schizophrenia or bipolar disorder it commonly triggers relapse. Taper under medical supervision.
Why does it make me so drowsy? Quetiapine blocks histamine receptors, and that effect predominates at low amounts. It usually eases over the first weeks.