I can truly sympathize with anyone that has to deal with veins that seem non-existant sometimes. After having an abscess from a missed shot 3 years ago, I decided I never want to go through that again, so I did my research, made some changes and I follow the harm reduction guidelines faithfully! I probably over prepare now but it's far better to do so than to have an abscess!
I realize the OP requested veins other than the arm. The saphenous vein in the leg is usually a great option. (see link below for leg vein chart) However the veins on top of the feet can unfortunately be rather painful. My preference is to try to keep my veins healthy and have done a good job of it so far,(knock on wood) so these tips apply to both arms and legs.
The first thing I now do is use a large cotton ball saturated with alcohol and swab the whole area. I usually do bicep curls for a couple minutes and then I feel all around the area I think looked good. I have come to believe that our eyes are actually secondary in finding a vein. For those of us with veins that roll, consider carefully entering the vein slightly from the side, still keeping the bevel side up. Once located, You may choose to use your hand to help prevent the vein from moving. <---- "anchoring" your skin, pulling it a bit taut to prevent vein movement, is more helpful than you might think! It's a solid part of what EMTs are taught and their goal is to register in 12 seconds! I know it helps me, but always stick with what feels right for you.
I always make sure I'm in a clean,comfortable, quiet, private place. I have everything I might need easily accessible before I start. I go in knowing that I will take my time and I don't poke around with my rig until I can feel a plump, ready vein that I'm reasonably certain that I can hit. I get jittery with anticipation so I often need to take a few deep breaths and get my Zen on! If your arm / leg is shaky be sure to have a place to support it. I know this sounds funny but I have a napkin warmer - don't laugh! (that thing fancy restaurants have so they can give you a warm, moist towel after dining - but I'm betting a small electric frying pan with a lid would work just as well.) I keep clean, bleached wash cloths and bottled water and have a warm wash cloth prepared inside the warmer to wrap my arm in if I'm not successful on my first attempt or if my veins are being elusive. If it's not needed for that, the warm wash cloth can feel soothing to gently apply after the injection. Drug use is a hedonistic behavior! - go the extra mile to ensure your experience rocks!
I also have the usual supplies - A bottle of Isopropyl (rubbing) alcohol, clean cotton balls and Q-Tips, a tube of neosporin and band aids, just in case. Then there's also a tourniquet, which is actually the old, very soft and flexible air line aquarium tubing that most Petsmarts still carry. (not the newer more rigid plastic- like type) and a stress ball. Sometimes I try everything mentioned, other times I'm good to go after the curls.
Dehydration is always a factor as well. If you know you'll be shooting up soon, or using amphetamines via any ROA, try to increase your fluid intake - beverages with caffeine or a lot of sugar, such as soda, can reduce the amount of fluid that your body actually retains. Opt for water, real coconut water and low cal sports drinks. Coconut water seems to be the best for hydration though it can be a bit expensive. As far as sports drinks go I like Powerade zero. Ideally keep a couple bottles of each on hand and of course keep drinking your water!
Be safe and enjoy!
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