How A Sanguivore Feeds

[This article is not intended to encourage blood-drinking or venipuncture. If you experience any symptoms, please see your doctor. Do not attempt phlebotomy without the required training and supervision from a medical professional as you could cause significant harm. Always be wary of what you are consuming, and donors should always be properly screened. It is shared both from personal experience and my observations with how other sanguivores feed. It is NOT a ‘how to’. For the purposes of this article, ‘sanguivore’ refers to those who appear to be biologically alike in terms of traits and needs.]

Sanguivores feed in a variety of ways. A polite and well-intentioned comment recently noted that many sangs use a lancet, and that they’d never heard of someone needing blood in significant quantities. While this is true for some, it is rarely true for sanguivores. Sanguivores employ a number of methods of extracting blood. Due to the volume often needed, this is most often done with venipuncture or with animal blood. I will attempt to elaborate a little more on the basics of sanguivore feeding.


This tends to be anywhere from 100ml a month to several pints a week. It depends entirely on the person. Some take the bare minimum so they aren’t at death’s door, some take as much as they can in order to thrive. A pint of human blood a month is commonplace. For the lucky ones, several pints of human blood a month has been achieved. For those who can access and thrive from animal blood, the number tends to be higher, including a quart in one sitting. Animal blood consumption can be far higher due to availability, from one pint every couple of weeks to two or three pints a week. Some prefer to take blood via. vacutainers, in which case it tends to be somewhat lower due to affordability issues; such as 50ml per week. Donors can only safely give around 450ml every 4-6 weeks, so any more than that requires several donors. 400ml roughly can be taken in a month. It is the responsibility of the sanguivore to ensure their donor gets plenty of fluids and has a high protein meal after donating. Significant quantities have been consumed in one sitting – several pints or more. I have not known this to cause stomach upset for anyone who has done so. Taking more than capacity is dangerous for all involved, in terms of health and legal risks.


A variety of methods are employed, which I will attempt to cover very basically below. These are things such as contact feeding, vacutainers, free bleeds, animal blood, cannulation, and blood bags. The most common method I’ve witnessed is vacutainers and a 21g butterfly needle. Donors should practice the same techniques as with the Red Cross. Drink plenty of fluids and eat plenty of food when donating blood. Lack of fluids make blood draws challenging and can lead to more painful sticks. All blood storage requires anticoagulant and refrigeration. Please note there are far more details to each of the methods requiring phlebotomy skills to make these methods safe; please do not attempt them.


Lancets can be the ‘go-to’ for beginner sangs whatever their need. It is a relatively safe and inexpensive way of drawing blood. A small prick on the tip of the finger will draw several drops of blood. Sterilizing the drawing site with rubbing alcohol is crucial. Gauze is used following the prick to apply pressure to the site. This is almost never enough for a sanguivore but it is a good way of putting ‘one foot in the water’ and building confidence to move on to methods that procure more blood. Diabetic lancets are too small, and thick skin medical lancets are preferred.

Contact Feeding

The next type of feeding after lancets is usually contact feeding. This is a way of achieving slightly greater yield without having to risk the dangers of phlebotomy. A scalpel is used to make a small incision on a part of the body that has dense muscle content and away from any dangerous areas; these can include the thigh, the back of the shoulder, or the chest. Once again, alcohol rubbing and sterilization is critical to donor safety. Caution is used when employing this method. A small but slightly deeper cut tends to yield more blood. Experimentation is helpful with contact feeding. It is always better to start with a very small, shallow cut and go from there (with permission of your donor).  For younger sangs, this method can result in more guilt because of the physical harm being done to procure blood. This tends to be one of the most ‘satisfying’ types of feeding, but with needs of many sanguivores, it isn’t sustainable. Blood can’t be stored, nor can it be taken over longer periods of time even with live-in donors. It would also result in many cuts and scars for the donor with high need; also not sustainable. Cuts are never done around major veins or arteries as this could result in serious harm to your donor. 


This is a common method employed by sanguivores. An 18g-21g butterfly needle is often the size used for this method as the median cubital vein in the inner elbow is the commonly used site. 21g (the smaller) needle tends to be the recommended size as it’s easier to work with, and a bigger size is generally not needed as it fills the same size vial all the same. Many can shy away from the vacutainer method as it is the first that many sanguivores have used that requires phlebotomy skills and sticking someone with a needle often evokes anxiety. This can be overcome with extensive training, courses and knowledge. The inner elbow is rubbed with alcohol to sanitize the site and tourniquet applied. Good practice includes wearing medical gloves for the procedure. I will not describe the details here as I do not want to encourage the untrained to practice this method. Suffice to say, the needle is inserted into the median cubital vein. Blood will ‘flash’ in the needle letting the user know that they have hit the vein. A vacutainer is inserted into the vacutainer holder at the end of tubing, and blood is pulled into the vacutainer by the vacuum. Anyone who has had blood drawn has seen this method. Different people use different types of vials, and different types of vials allow for different lengths of storage. Vials and the equipment tend to be expensive. Commonly used vials are green tops (heparin – allows storage for roughly one week) and purple tops (EDTA –  allows storage for roughly one month). This method, done correctly, causes minimal to zero pain for the donor. There are also safety concerns to be taken into consideration regarding additives when using the different types of vials. For further information on the vial additives and their safety for human consumption, please see ‘Additives Used in Blood: Variable Safety for Human Consumption‘.

Animal blood

Some sanguivores procure animal blood in the absence of human donors or to supplement their intake due to high need. Arrangements can be made with local farmers. Joining agricultural groups and sustainable farming communities can be beneficial to this cause; I’ve had many quarts offered to me for $10 during harvest season, organic and fresh. Slaughterhouses and some butchers can be a resource as well. Animal blood can be obtained from a large number of Asian grocers. Cooking with animal blood is so normal in Asian cuisine that no one cares that you buy it, or how much. This tends to be of lesser quality and heavily salted to prevent coagulation. Buying animal blood online is doable from places such as PhilAm Foods (now known as FilStop). Sources need to be carefully vetted when consuming raw animal blood as animal blood can contain a number of nasties, such as parasites.

Blood bags

Blood bags contain CPDA, an anticoagulant which stores blood for roughly a month and is safe for human consumption. Blood bags require a large 16 gauge needle. Unlike vacutainers, there is no vacuum to pull blood into the bag; only gravity. Because of the bag needing a pint to be full and the lack of a vacuum, the needle has to be sufficiently large to extract enough blood in time. If the stick is not correct or the donor is having bad flow making it take too long, blood can coagulate in the tubing making filling the bag impossible. Good practice includes putting an electronic scale on the floor with the bag placed on top, the donor sitting upright in a chair and letting the blood flow with gravity into the bag, as well as prior application of a tourniquet, sterilization of the area with rubbing alcohol and wearing medical gloves. The electronic scale allows for precise measurement and donating can stop once the 450ml capacity is reached, as it can be difficult to gauge just exactly when the bag is full or not. It prevents taking too much blood. Due to the size of the needle, this method can be intimidating for both sanguivore and donor alike; yet it is a very cost-effective way of accumulating significant volumes of human blood and storing them for a longer amount of time. The stick can be more painful and described as a ‘sting’. As a cost comparison, estimated prices can go from $5 for a blood bag to store 450ml of blood, compared to a crate of 100 x 10ml vacutainers (that can store roughly twice that amount) for $70+. Some sangs then drink directly from the bag like a juice drink, some prefer to drink it in a glass like coffee. With the inexperienced and untrained, attempting this method can cause significant damage.

Cannulation (IV)

Anyone who has ever been to a hospital should be familiar with IntraVenous (IV) cannulation. The needles can vary in size depending on which part of the body they are to be used on. The difference is that these contain a flexible cannula which remains in the vein and a ‘tap’. These are used in a hospital setting due to the flexibility of the cannula meaning it can remain in someone’s vein for a longer period of time versus the stick and removal of a needle, particularly if over a longer period of time and taking blood is intermittent. Sanguivores have sometimes used these when taking a lot of blood, but it is an advanced and particular technique. Untrained attempts are dangerous and with respect to donor safety, should never be attempted.

Free Bleeds

Often noted as one of the most satisfying types of feeding along with contact feeding. Most of the methods described above can turn into a free bleed. The end of tubing with the vacutainer method can be detached from a vacutainer holder and taped down to the forearm, allowing blood to flow down the forearm. Other methods include cutting the tubing with a blood bag and taping it in place, allowing it to flow freely down the forearm (this would flow very quickly, so it couldn’t be for long), or ‘turning on the tap’ with a cannula. Of course, this gets messy quickly so towels are used. Sangs should never place their mouths at the other end of the ‘hole’ as this could lead to complications and infections for the donor; only licking it up from the forearm. 


I’ve heard once or twice of some sanguivores using a syringe to extract blood and then using that to fill a cup. In my experience, the long, straight needle can be unnecessarily tricky to use and it’s easier to just use a butterfly needle.

Complications and Risks

Needless to say, almost all of these methods carry with them severe risks. With cutting, cuts can go too deep and seriously injure a donor or worse. All types of venipuncture carry significant risks. These can include a hematoma, embolism, phlebitis, syncope, arterial puncture, and more. Hematomas can be treated with ice, pressure and elevation. Again, this should never be attempted without the required training and experience. Many sanguivores, out of necessity, have undergone professional training and courses, along with many years of practice. Uncooked animal blood can contain parasites among other contaminants, so drinking it carries risks.

Do not try this at home.

[Once again, disclaimer; this article is intended only to illustrate the lives of sanguivores and the techniques/resources employed to thrive with high need. It does not intend to speak for all sanguivores, but only observations over a prolonged period of time. Be wary of anything you consume and properly screen donors. It does not constitute medical advice or encourage anyone to replicate the techniques above. Any attempt to recreate anything mentioned in this article is done so at the reader’s own risk and volition.] 

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