Visible blue veins on your thigh are concerning, especially since they make your legs look ugly. The blue veins are often, but not always, associated with tiny spider veins. The concern is whether or not their presence means something is wrong with your veins. While it's difficult to say for sure without an in-person examination, blue veins can be perfectly normal or they could be an early indicator of a vein condition.
Here are some questions you can ask yourself to get an idea about the potential cause, and if they are something over which you should be concerned.
Are veins visible in other places in your body? People who have lighter complexions are able to see the veins more easily through the surface of the skin. If this is the case, visible blue veins on your legs could be perfectly normal.
If the vein is pressing against the surface of the skin so that it pops out, that isn't normal and indicates the presence of a vein condition. With a vein condition, stagnant blood pools in the vein and presses against the vein walls, enlarging them to the point that they can be seen beneath the surface of the skin. Veins that are straight are usually but not always normal.
When there is abnormal pressure in those veins due to a vein condition, the spider veins tend to burst open and spread out as a fan. These usually appear on the inner thigh, or on the outer thigh between the knee and the thigh.
When a vein condition is present, it typically has other symptoms that you don't see and that are usually disregarded as normal or "part of getting older." Symptoms that are specific to a visible cluster of veins include burning, stinging, throbbing pain, or itching where the veins are. With a vein condition, these symptoms typically worsen in the evening and night and improve in the morning. Invisible symptoms include leg pain, leg aching, leg swelling, fatigue, poor sleep, itching legs, burning/stinging feet, cold feet, restless leg syndrome, leg cramps, and more. With treatment, these conditions resolve themselves.
The good news is that when visible blue leg veins are the result of a vein condition, treatment makes a significant difference both to improve the appearance and relieve the symptoms. The best way to get it all sorted out is to do a vein circulation screening. Vein treatments are covered by insurance, and the blue veins on your thighs will go away.