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What Led to My Near-Fainting Episode During a Blood Test?

12/17/2025, 3:40:20 PMMale25-34

A few years back, I experienced something quite surprising while getting blood work done, and I'm still trying to understand it. At the time, I was a healthy 30-year-old woman with a normal weight. Despite having multiple chronic conditions—such as Hashimoto's disease, fibromyalgia, Ehlers-Danlos syndrome, Postural Orthostatic Tachycardia Syndrome, generalized anxiety disorder, and PTSD—I typically have no problems with blood tests. I undergo these tests biannually for my thyroid levels, and while I don’t particularly enjoy needles, they don’t fill me with anxiety. Blood draws have always been a routine process for me until one fateful occasion. As soon as the needle pierced my skin, I suddenly felt dizzy, my skin turned pale, and I became cold and sweaty. This all transpired instantly, not after the blood collection was completed. The phlebotomist promptly called for a nurse when she noticed my condition, as she still needed to collect several vials of blood. I had to lie down for about thirty minutes and hydrate extensively before I could safely make my way home. Since then, I haven't had a similar episode. What could have triggered such a reaction?

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Answers (1)

Cony

12/17/2025, 3:40:39 PM

OpenHealth AI

It sounds like you experienced a vasovagal syncope episode during your blood test, which can happen even to people who are generally healthy. This reaction isn't uncommon and often occurs when the body overreacts to certain triggers, like the sight of blood, the pain from the needle, or even the act of lying down during the procedure.

Explanation:

When the needle is inserted, the body’s nervous system can react by slowing the heart rate and lowering blood pressure, leading to symptoms such as dizziness, pallor, and sweating. This type of fainting spell is typically brief and resolves quickly once you lie down and hydrate. Considering your chronic conditions—especially Ehlers-Danlos syndrome and Postural Orthostatic Tachycardia Syndrome (POTS)—this could have made you more prone to such a reaction.

Next Steps:

  1. Hydration Before Tests: Drink water before your blood tests. This can help improve blood volume and reduce dizziness.

  2. Communicate with Healthcare Providers: Always inform the healthcare staff about any history of fainting or specific Conditions (like POTS) to allow for extra precautions during blood draws, such as lying down or adjusting the procedure.

  3. Breathing Techniques: Practice deep breathing or relaxation techniques before your appointment. This can help soothe anxiety and prevent triggering a vasovagal response.

  4. Monitor Your Body: Pay attention to how you feel before and during procedures. If you start to feel dizzy or lightheaded, speak up immediately.

  5. Follow-Up if Needed: If you experience any similar symptoms in the future or have concerns about your health, keeping a log of your symptoms can help identify patterns or triggers to discuss with your doctor when necessary.

Stay aware of your body's signals and take these small but effective steps to make future blood tests more comfortable for you. If you encounter any further issues or changes in your health, consider discussing this with your healthcare provider.

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