21, male, is this hair loss just androgenic alopecia? (Photos)

Hello jimjohnboi -- from the look of the photos you posted, your hair loss does not appear to be classic androgenetic alopecia (AGA) or "patterned" hair loss, also known as male-pattern baldness. That is by far the most common type of hair loss affecting men, but there are other types. In AGA, there is a very predictable pattern of loss and it always spares the back and the sides, known as the "permanent zone". Even in the most advanced stages of AGA, the back and the sides are spared. Any time there is loss in the permanent zone, a different diagnosis should be sought.
There is another type of hair loss called Diffuse Unpatterned Alopecia, or DUPA, where the loss does not follow the classic and predictable pattern. The hair loss tends to be more diffuse and can affect the permanent zone on the back and sides. When there is hair loss on the back and the sides, especially when it is present in that area on the sides behind the ear, this makes me think of DUPA. Also in your case it seems to be affecting the right side more than the left. When hair loss is patchy like that, diagnoses like alopecia areata have to be considered. In some cases a biopsy can be helpful in making a diagnosis.
Just based on these photos, it seems that DUPA is likely. To answer your question about the hair loss prevention medications such as finasteride and minoxidil, yes, these could definitely be helpful in slowing down the progression of the hair loss. Other preventative measures such as Low Level Laser Therapy and PRP can also be helpful in these cases. I would recommend seeing a hair loss specialist for a closer examination and to discuss treatment options.

Dear RealSelf member 0928793,
You're correct in that you have diffuse or generalized thinning. I'd recommend an in person evaluation. Two etiologies might cause this picture, DUPA and Alopecia Incognita. A thorough medical history and physical are needed, (and maybe even a scalp biopsy and lab), to delineate the difference between the conditions.

Appears to be DUPA (diffuse alopecia). It is often best treated with combination finasteride and minoxidil. A biopsy can confirm with a board-certified dermatologist. You could also test for a thyroid condition. Scalp exam can identify inflammation or other causes and confirm with a simple biopsy.