Other psychostimulants and nootropics (local classification)
ATC code: N06BX-GLYCINE (Glycine (as a marketed «nootropic») – local code)
Glycine is a natural amino acid and inhibitory neurotransmitter in the spinal cord and brainstem. In sublingual tablets, the manufacturer claims nootropic, sedative, and stress-protective effects. Bioavailability after sublingual administration is questionable — glycine is actively metabolized in the liver and synthesized locally in the CNS. The blood-brain barrier permits limited glycine entry. Independent RCTs of clinical efficacy for the claimed indications are absent.
Not recommended
For children with developmental delay, hyperactivity, sleep disturbance, or academic underperformance, glycine is not mentioned in international pediatric guidelines. Effective approaches are behavioral therapy, specialist-led intervention, and stimulant medication for confirmed ADHD on strict indication.
Not recommended
Glycine 1–2 g sublingually in acute ischemic stroke is not mentioned in 2019 or 2021 guidelines. Proven therapies are thrombolysis and thrombectomy where indicated. In the acute phase, sublingual dosing is impossible due to impaired consciousness and aspiration risk.
Not recommended
Glycine for stress, anxiety, or sleep disturbance in adults and children is not mentioned in or mental health guidelines. No evidence base. Standard therapy for clinical anxiety is psychotherapy (CBT) and SSRIs; subclinical anxiety is managed non-pharmacologically (physical activity, sleep hygiene, caffeine restriction).
Not recommended
— Asthenic syndrome: «Asthenic syndrome», «nervous fatigue», and «reduced performance» as clinical indications do not exist in international medicine. Glycine is not mentioned in this setting in international guidelines. Chronic fatigue warrants differential workup: anemia, B12 deficiency, hypothyroidism, depression, obstructive sleep apnea, chronic infections.
Manufacturer allows use at standard doses. No international recommendations. Glycine as a natural amino acid is nutritionally safe, but offers no therapeutic benefit in pregnant patients for the claimed indications.
Compatible with breastfeeding.
glycine (as a marketed «nootropic») is evaluated for the following indications with varying evidence strength: Developmental delay in children (evidence tier F), Stress and anxiety (evidence tier F), Ischemic stroke (evidence tier F). See the full indication matrix with dosing and citations above on this page.
Common side effects of glycine (as a marketed «nootropic») (≥ 1 in 100): Allergic reactions (rare). See the Safety section for uncommon and serious reactions.
Manufacturer allows use at standard doses. No international recommendations. Glycine as a natural amino acid is nutritionally safe, but offers no therapeutic benefit in pregnant patients for the claimed indications.
Compatible with breastfeeding.
glycine (as a marketed «nootropic») is contraindicated in: Hypersensitivity. Full list in the Safety section.
there is no international evidence base for these effects from sublingual tablets. Patient-reported effects are most plausibly explained by placebo.
international pediatric guidelines do not support glycine for childhood anxiety or stress. Sleep hygiene and physical activity are the foundation; pronounced anxiety warrants child psychologist input.