Molindone, sold for decades as Moban, is one of the more unusual entries in the first-generation antipsychotic catalog. Chemically, it is a dihydroindolone — structurally distinct from the phenothiazines, butyrophenones, and thioxanthenes that make up most of the older antipsychotic family. Clinically, it is best known for one thing: unlike most antipsychotics, it tends to cause weight loss rather than weight gain. That property, plus a generally moderate side effect profile, kept it in use through the 1980s and 1990s. It was discontinued in the US in 2010, then returned to the market several years later through different manufacturers.
Molindone is a mid-potency first-generation antipsychotic notable for causing weight loss rather than gain, with a moderate EPS profile and a niche role in modern practice.
What molindone is
Molindone is a dopamine D2 receptor antagonist, with relatively little anticholinergic, antihistaminic, or alpha-adrenergic activity. It is generally classified as a mid-potency first-generation antipsychotic. The NCBI StatPearls molindone overview summarises its profile in clinical terms.
The weight effect
Most antipsychotics — first-generation and second-generation alike — cause some weight gain. Molindone is one of the few that does not, and may cause modest weight loss in some patients. The reason is not fully understood; it likely involves its lack of histamine H1 blockade (which drives appetite stimulation in olanzapine, quetiapine, and others) combined with mild stimulant-like effects in some patients. For people whose weight has been a major problem on other antipsychotics, this property has historical interest.
Indications
The FDA-labelled indication is the management of schizophrenia. Molindone is not commonly used today for other conditions.
Dosing
Typical dosing is 50 to 100 mg/day for moderate symptoms, up to 225 mg/day for severe presentations. It is usually divided into 3 or 4 daily doses. Older patients and those with sensitivity require lower starting doses. Like most first-generation antipsychotics, molindone is started at lower doses and titrated based on response and tolerance.
Side effect profile
Movement effects
Molindone causes EPS, akathisia, and tardive dyskinesia at rates comparable to other mid-potency first-generation antipsychotics. Acute dystonia, parkinsonism, and akathisia all occur. See our overview of EPS.
Sedation
Generally mild compared with low-potency typicals like chlorpromazine. Some patients describe it as relatively activating.
Weight
The unusual effect — neutral or slight weight loss in many patients. This can be helpful for those switching from heavier-weight-gain antipsychotics.
Anticholinergic effects
Mild — dry mouth, blurred vision, and constipation occur but are typically less prominent than with phenothiazines.
Hyperprolactinemia
Like other D2 blockers, molindone raises prolactin levels with potential for menstrual changes, galactorrhoea, sexual dysfunction, and over the long term, possible bone density effects. See hyperprolactinemia article.
Cardiovascular effects
Modest QTc prolongation possible. Orthostatic hypotension is uncommon at typical doses. See QT prolongation article.
Less common but serious effects
- Neuroleptic malignant syndrome — rare and life-threatening
- Tardive dyskinesia — long-term cumulative risk
- Lowered seizure threshold — modest, similar to other antipsychotics
You develop fever with severe muscle stiffness, confusion, fast heart rate, and unstable blood pressure — these can signal NMS. Also seek care for new sustained involuntary movements of the face, tongue, or limbs.
Where molindone fits today
Molindone is not a first-line drug in modern algorithms. It plays a role in a few situations:
- Patients who responded well to it before its market discontinuation and want to return to it
- Patients for whom weight gain on multiple other antipsychotics has been a barrier to adherence
- As an option in resource-limited settings where cost matters
- Occasional use in adolescent populations — the TEOSS trial (Treatment of Early-Onset Schizophrenia Spectrum Disorders) compared molindone with olanzapine and risperidone in youth and found similar efficacy with less metabolic burden
The TEOSS trial
Published in the American Journal of Psychiatry in 2008 (Sikich et al.), TEOSS was a NIMH-funded comparison of molindone, olanzapine, and risperidone in 119 youth aged 8 to 19 with schizophrenia or schizoaffective disorder. The three drugs showed similar efficacy on positive and negative symptoms, but olanzapine and risperidone caused much more weight gain. Molindone caused EPS more frequently. The result reinforced the value of molindone as an option specifically when weight gain is the limiting concern, particularly in younger patients.
Drug interactions
Molindone has fewer drug interactions than many antipsychotics. It does not significantly inhibit or induce CYP enzymes. Combining with other QT-prolonging or seizure-threshold-lowering drugs requires caution.
Who tends to do well on molindone
- People for whom weight gain has derailed prior antipsychotic trials
- People with stable schizophrenia who responded to it historically
- People with metabolic concerns who can tolerate the EPS risk
- Adolescents in some scenarios where weight matters particularly
Who might choose differently
- People with prior bad EPS or tardive dyskinesia
- People needing once-daily dosing (molindone is 3 to 4 times daily)
- People with significant cardiac history
- People who respond well to and tolerate second-generation alternatives
Practical questions to ask your prescriber
- Why molindone specifically rather than a newer agent?
- What schedule will work for me — twice daily or more?
- What movement side effects should I watch for?
- Will we monitor weight even though it is generally stable on molindone?
The big picture
Molindone is a niche drug — and it has earned that niche. For people whose treatment history is dominated by weight gain on other antipsychotics, it offers a genuinely different metabolic profile. The cost is a higher EPS burden and a less convenient dosing schedule. Like every antipsychotic decision, the right answer depends on your symptom picture, prior trials, weight history, and what you most want to avoid going forward. That conversation belongs with a prescriber who knows your full story.
This article is for educational purposes only and is not medical advice. Information is summarised from publicly available FDA labelling and peer-reviewed literature. Always consult your prescribing clinician before starting, stopping, or changing any medication.