Do uv rays affect those taking medications more?

It depends on the medication. Certain medications such as thiazide diuretic, doxycycline, etc. make the skin more susceptible to UV ray. However, UV ray does not enhance or reduce the therapeutic effects of those medications.

Yes, there are many medicines that make your skin much more sensitive to UV light (e.g. fluoroquinolones, tetracyclines, sulfa drugs). https://duckduckgo.com/?t=ffab&q=photosensitizing+drugs+list&ia=web. There are also several plants that can act as photosensitizers. Any of these agents can let you sunburn more quickly & more severely than you normally would. Use usual sun protection products.

Various medications can serve as photosensitizers, causing one to become sunburned more frequently and more severely. Speak with your pharmacist about those interactions { meds and sunlight}