Low-dose atropine eye drops for myopia: what the LAMP trial shows
Atropine eye drops at low concentration are the main pharmacological option for slowing myopia in children. The question clinicians and parents ask is which concentration, and the clearest answer comes from the Low-Concentration Atropine for Myopia Progression (LAMP) study.
How atropine works
Atropine is a muscarinic antagonist. At full strength it dilates the pupil and relaxes focusing. How it slows eye growth is not fully understood, but it is not thought to act through focusing alone. Low concentrations aim to keep the growth effect while limiting glare and near blur.
What the evidence shows
LAMP was a randomised, double-masked, placebo-controlled trial of 438 children aged 4 to 12 in Hong Kong. Children received 0.05%, 0.025% or 0.01% atropine, or placebo, nightly in both eyes for a year.
| Group | Myopia progression (D) | Axial elongation (mm) |
|---|---|---|
| 0.05% atropine | -0.27 | 0.20 |
| 0.025% atropine | -0.46 | 0.29 |
| 0.01% atropine | -0.59 | 0.36 |
| Placebo | -0.81 | 0.41 |
The response followed concentration, and 0.05% was the most effective. Side effects also followed concentration: photopic pupil size increased by about 1.0 mm with 0.05% against 0.5 mm with 0.01%, and accommodation fell by about 2.0 D against 0.3 D. Visual acuity and vision-related quality of life were not affected in any group (Yam et al., 2019).
An honest read of the evidence
- At 0.01%, the effect on axial length in the first year was small (0.36 mm against 0.41 mm with placebo). Refraction alone flatters this concentration.
- LAMP enrolled Chinese children. Trials in other populations have given mixed results for 0.01%, and the best concentration for New Zealand children is not established.
- Rebound after stopping, how long to treat and how to taper are still being worked out.
- In New Zealand, low-dose atropine is typically supplied as a compounded preparation, so formulation and stability matter.
Myopia research at NZERC
Open questions include combination with optical treatments, dose selection outside East Asian populations and formulation. The New Zealand Eye Research Centre (NZERC) measures axial length and choroidal thickness and vascularity and welcomes approaches from pharmaceutical sponsors. See our information for sponsors and CROs. Families can register their interest in myopia studies. For assessment and treatment, contact our affiliated clinical practice, Rose Optometry.
References
- Yam JC, Jiang Y, Tang SM, et al. Low-Concentration Atropine for Myopia Progression (LAMP) Study: a randomized, double-blinded, placebo-controlled trial of 0.05%, 0.025%, and 0.01% atropine eye drops in myopia control. Ophthalmology 2019;126(1):113-124. doi:10.1016/j.ophtha.2018.05.029
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