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    Ammonia

    Risks

    If the sample is taken from a vein

    There is very little chance of a problem from having a blood sample taken from a vein.

    • You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for several minutes.
    • In rare cases, the vein may become swollen after the blood sample is taken. This problem is called phlebitis. A warm compress can be used several times a day to treat this.
    • Ongoing bleeding can be a problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can make bleeding more likely. If you have bleeding or clotting problems, or if you take blood-thinning medicine, tell your doctor before your blood sample is taken.

    If the sample is taken from an artery

    There is little chance of a problem from having a blood sample taken from an artery.

    • You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for at least 10 minutes after the needle is removed (longer if you have bleeding problems or take blood thinners).
    • You may feel lightheaded, faint, dizzy, or nauseated while the blood is being drawn from your artery.
    • Ongoing bleeding can be a problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and other blood-thinning medicines can make bleeding more likely. If you have bleeding or clotting problems, or if you take blood-thinning medicine, tell your doctor before your blood sample is taken.
    • On rare occasions, the needle may damage a nerve or the artery, causing the artery to become blocked.

    Though problems are rare, be careful with the arm or leg that had the blood draw. Do not lift or carry objects for about 24 hours after you have had blood drawn from an artery.

    WebMD Medical Reference from Healthwise

    Last Updated: /2, 14 1
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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