Methylphenidate
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Methylphenidate: From ADHD and Narcolepsy to Faciodigitogenital Syndrome
One-Sentence Summary
Methylphenidate is a central nervous system stimulant, originally used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. The TxGNN model predicts it may be effective for faciodigitogenital syndrome (score 99.998%), but no clinical trials and no publications currently support this prediction, so it is a model output only. Among the other top-ranked predictions, only a few have any indirect evidence, and none shows direct proof of therapeutic benefit.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | ADHD, narcolepsy (the licence records list no indication text; these indications come from the knowledge graph) |
| Predicted New Indication | Faciodigitogenital syndrome |
| TxGNN Prediction Score | 99.998% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 15 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the compiled data. Based on known information, methylphenidate blocks the dopamine and norepinephrine transporters, which raises these neurotransmitters in the brain. This is the basis of its effect in ADHD and narcolepsy. Recent imaging studies in adults with ADHD support its action on both transporters.
Faciodigitogenital syndrome is a rare developmental disorder. No plausible mechanistic link to dopamine/norepinephrine reuptake inhibition is supported by the data. At most, methylphenidate might offer symptomatic help for co-occurring ADHD-like features, and this is not evidenced. The high score is best read as a model association and not as a biological rationale.
Other predictions reviewed (ranks 2-10):
| Rank | Predicted Indication | Score | Evidence Level | Assessment |
|---|---|---|---|---|
| 2 | Chondromyxoid fibroma | 99.991% | L5 | No data; likely a knowledge-graph artifact |
| 3 | Specific developmental disorder | 99.988% | L4 | Literature is mostly about ADHD (already approved); indirect |
| 4 | Dysthymic disorder | 99.109% | L4 | Only ADHD with comorbid subsyndromal depression studied; indirect |
| 5 | Trichotillomania | 98.825% | L4 | Case reports suggest stimulants may cause or worsen it |
| 6 | Cerebellar ataxia | 98.394% | L4 | Case-level and imaging data only; no improvement in ataxia shown |
| 7 | Autosomal dominant cerebellar ataxia | 98.379% | L5 | Only a diagnostic imaging study |
| 8 | Spinocerebellar degeneration with slow eye movements | 97.567% | L5 | Imaging studies only |
| 9 | Benign paroxysmal torticollis of infancy | 97.514% | L5 | No data |
| 10 | Insomnia | 97.512% | L4 | Stimulant tends to worsen sleep; trials study sleep as a side effect |
Clinical Trial Evidence
Currently no clinical trials are registered for faciodigitogenital syndrome.
For reference, trials were found for two lower-ranked predictions, and neither tests methylphenidate for the predicted condition itself:
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00552266 | Phase 4 | Unknown | 30 | Methylphenidate in children with ADHD and comorbid trichotillomania; population is ADHD, so only indirectly informative |
| NCT01393574 | Phase 4 | Unknown | 46 | Melatonin vs methylphenidate in children with ADHD and sleep difficulties; does not test methylphenidate for insomnia |
| NCT00989950 | N/A | Completed | 26 | Open-label study of methylphenidate patch wear-time and sleep in children with ADHD; sleep as a treatment effect |
| NCT02638168 | Phase 4 | Terminated | 3 | Evening immediate-release methylphenidate and sleep in ADHD; terminated with 3 participants, so essentially no usable evidence |
Literature Evidence
Currently no related literature is available for faciodigitogenital syndrome.
The closest literature relates to the rank 3 prediction (specific developmental disorder) and rank 5 prediction (trichotillomania). It mainly reflects the existing ADHD indication:
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 40527386 | 2025 | Cohort | Prog Neuropsychopharmacol Biol Psychiatry | Age-dependent effects of cumulative methylphenidate exposure on brain structure and symptoms in youth with ADHD (longitudinal MRI) |
| 41128391 | 2026 | Cohort | Psychiatry Clin Neurosci | Dual-tracer PET showing effects of extended-release methylphenidate on dopamine and norepinephrine transporters in adults with ADHD |
| 41655471 | 2026 | Cohort | Psychiatry Res | Multi-cohort meta-analysis of polygenic prediction of ADHD treatment response |
| 42218703 | 2026 | Systematic Review | J Cutan Med Surg | Systematic review of hair loss in patients with ADHD |
| 21586916 | 2011 | Cohort | Clin Neuropharmacol | Preliminary report of methylphenidate in children with ADHD and comorbid trichotillomania |
| 28492426 | 2017 | Case report | J Clin Psychopharmacol | Trichotillomania arising in ADHD under methylphenidate treatment |
| 28394174 | 2017 | Case report | J Child Adolesc Psychopharmacol | Modified-release methylphenidate-related trichotillomania in a boy with autism spectrum disorder |
| 31984712 | 2020 | Case report | Arch Argent Pediatr | Two paediatric cases of new-onset trichotillomania during stimulant treatment |
| 19627998 | 2009 | Review | Neuropharmacology | Overview of the neurobiology of ADHD |
| 22923783 | 2015 | Review | J Atten Disord | Review of methylphenidate efficacy, safety and mechanisms in adult versus juvenile brain |
Singapore Market Information
Methylphenidate has 15 valid single-ingredient registrations in Singapore, all oral. The licence records contain no approved indication text. The five main authorizations are listed below:
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN12098P | Concerta Extended-Release Tablet 36 mg | Film-coated tablet | Not stated in the records |
| SIN17020P | Neurofind Prolonged Release Tablets 18 mg | Film-coated, extended-release tablet | Not stated in the records |
| SIN14754P | Medikinet MR Capsules 10 mg | Delayed-release pellet capsule | Not stated in the records |
| SIN12351P | Ritalin LA Capsule 20 mg | Capsule | Not stated in the records |
| SIN03542P | Ritalin Tablet 10 mg | Tablet | Not stated in the records |
Safety Considerations
- Contraindications suggested by the knowledge graph (these are graph associations, not package insert text): hypertension, coronary artery disease, myocardial infarction, stroke and other cerebrovascular disorders, sudden cardiac arrest, heart conduction disease, epilepsy, bipolar and other major affective disorders, psychotic and schizophrenia-spectrum disorders, substance abuse/dependence, anorexia nervosa, glaucoma, hyperthyroidism/thyrotoxicosis (including Graves disease), thrombocytopenia, leukopenia, and anaemia/haemoglobinopathy.
- Drug Interactions: The interaction search returned 100 records. Bupropion is rated Major. Moderate interactions include isometheptene, ephedrine, epinephrine, and the bowel-preparation agents polyethylene glycol (3350 with electrolytes), picosulfuric acid and sodium sulfate. Many others are of unknown severity.
- Signals from the literature: Case reports link stimulant treatment to new-onset or worsened trichotillomania. Stimulants can also worsen sleep onset and duration.
Please refer to the package insert for the official warnings, as these were not available in the compiled data.
Conclusion and Next Steps
Decision: Hold
Rationale:
- The top prediction (faciodigitogenital syndrome) is supported only by a model score. There are no trials, no literature, and no plausible mechanistic link (Evidence Level L5).
- Among the other top predictions, the evidence is indirect, reflects the existing ADHD indication, or points to a possible harm (trichotillomania, insomnia). None justifies efficacy development at this stage. Dysthymic disorder, cerebellar ataxia and specific developmental disorder may be worth considering as research questions.
To proceed, the following is needed:
- Mechanism of action data and a documented biological rationale linking methylphenidate to the predicted condition
- The HSA package insert, including approved indications, warnings, and contraindications
- Direct clinical studies in the predicted condition (none exist at present)
- A safety evaluation for trichotillomania and sleep disturbance if these predictions are pursued
- Route and formulation compatibility assessment
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.