Monitoring of patients taking canthaxanthin and carotene: an electroretinographic and ophthalmological survey.
1. Patients who have taken canthaxanthin and beta-carotene to avert phototoxicity have been monitored by electroretinographic testing. 2. Patients took the compounds only during the summer months, but were monitored for more than 1 year to determine if seasonal changes in the ERG were visible. 3. The characteristic refractile retinal crystals reduced during the winter. 4. The scotopic b-wave amplitude increased during the winter, whether evoked by red or blue flashes. 5. No other ERG parameter altered. 6. Changes noted in 3 and 4 above are reversible. 7. A dose/ERG-amplitude response relationship was established, but no correlation between blood level or total cumulative dose and b-wave amplitude could be found. 8. It is suggested that the Müller cells concentrate canthaxanthin and this is the mechanism which affects the ERG.
Arden
G B
GB
Electrodiagnostic Department, Moorfields Eye Hospital, London, UK.
Oluwole
J O
JO
Polkinghorne
P
P
Bird
A C
AC
Barker
F M
FM
Norris
P G
PG
Hawk
J L
JL
D000368:Aged; D016644:Canthaxanthin; D002338:Carotenoids / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000494:pharmacology*; D004596:Electroretinography; D005260:Female; D006801:Humans; D008991:Monitoring, Physiologic; D009883:Ophthalmic Solutions; D012160:Retina / Q000187:drug effects
D009883:Ophthalmic Solutions; D002338:Carotenoids; D016644:Canthaxanthin