Dear Poppy: Not sure for what purpose you wanted the evening primrose oil for (seems to have a wide variety of medicinal usages), but if you were seeking menstrual cramp relief you can also try hibiscus flowers, which grows prolifically in Kathmandu gardens and is also available in powder form in the shop opposite the big apartments in Bishalnagar. Boil water, put the red petals, add lime juice so water turns pink, strain, and drink. The tea cures cramps within 30 minutes.
I recently wrote about how rudrapushpam (its Sanskrit/Ayurvedic name) was rated the best antiviral for avian flu amongst many different teas, so I assume it also decimates the coronavirus. It does lower blood sugar so one cup of mild tea per day is enough.
All best, Sushma