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Lesson 8) And I Get Bigger (Lab #2: Swelling Solution)

So sorry for the delay in getting things started today, class. In today's lesson, we will be completing your second lab of Potions, Year Two. We will be brewing what is known as the Swelling Solution, a potion that causes living tissue with which it comes in contact to swell and expand.


The Swelling Solution is a rather older potion, dating back in its current form all the way to the 16th century, when Greek potioneer Pavlos Efives was experimenting with potions to increase his petite 1.5m frame (that is about 4’11”). Although the potion did not have the desired effect, as it only made him swell up like a balloon rather than permanently increasing his diminutive stature, it has remained popular particularly with pranksters since that time. The Deflating Draught was not invented until the mid-18th century. Until that time, those who experienced magical swelling either had to utilize a charm to reverse the effects, or had to wait until they wore off on their own.

This potion is generally not too difficult to brew as long as you pay careful attention to your timing and how well you crush the necessary ingredients before adding them to the cauldron, but it is important to leave the potion simmering on a low heat for thirty seconds after adding the bat spleen and stirring before turning the heat back up to complete the brewing process. If you do not leave it on low for this interval, then it will begin to emit a putrid-smelling canary yellow smoke and will burn through your cauldron. Any contact with a failed potion of this nature will result in painful rashes and occasionally leave scales on the unfortunate victim.

Swelling Solution

Estimated Brewing Time:
Pewter cauldron: 55 minutes and 50 seconds
Brass cauldron: 50 minutes and 50 seconds
Copper cauldron: 41 minutes and 20 seconds

500 mL of water
2 tablespoons of nettles
3 pufferfish eyes
1 bat spleen
1 tablespoon of Flobberworm mucus


  1. Add 500 mL of water to your cauldron and bring the heat to 310 Kelvin (37°C/98°F).
  2. Add two tablespoons of nettles and three pufferfish eyes to your mortar.
  3. Crush the nettles and pufferfish eyes until it forms a medium fine powder. Please make sure it is evenly crushed as well and there are no chunks in the mixture.
  4. Add two tablespoons of this mixture to the cauldron.
  5. Bring the cauldron to 380 Kelvin (107°C/224°F) for 20 seconds. Reduce heat back to 310 Kelvin (37°C/98°F).
  6. Stir two times in a clockwise direction.
  7. Leave the potion to brew for 30 minutes. The potion will now be a teal color and the smoke will be a pale yellow. (For a brass cauldron, this would be 27 minutes, and for a copper cauldron, this would be 24 minutes and 18 seconds.)
  8. Add one bat spleen to the cauldron.
  9. Stir four times in a counter-clockwise direction.
  10. Bring the heat up to 350 Kelvin (77°C/170°F) for 30 seconds. Reduce heat back to 310 Kelvin (37°C/98°F).
  11. Leave the potion to finish brewing for 20 minutes. (For a brass cauldron, this would be 18 minutes, and for a copper cauldron, this would be 16 minutes and 12 seconds.)
  12. Remove cauldron from the heat and allow the potion to cool for 5 minutes. The potion should now be a dark turquoise with ripples of black running through it. It may smell a little like parsley.
  13. Stir in about one tablespoon of Flobberworm mucus with a wooden stirrer. A little more or less can be added depending on how thick you want your solution. Most prefer it a little runnier.
  14. Use a funnel or a Siphoning Charm to transfer the potion into a vial to label and store.

Usage Notes: The Swelling Solution is best stored on a window ledge in direct sunlight and does better in warm conditions. Unfortunately, this exposure to thermal energy means that the shelf life of the Swelling Solution is a little shorter than many other potions. This potion should only be stored for up to four months before it should be considered expired and a new potion brewed.

Side Effects: Allergic reactions to this potion are rare, but some with allergies to nettles do experience rashes and flaky skin when applying it. The potion should only be applied topically, and should never be applied to the face or near the eyes. If the potion does get into the user’s eyes, they should rinse their eyes immediately and see a medical professional. The potion should never be applied over cuts, lacerations, or broken skin. The Swelling Solution should never be swallowed, and medical attention should be sought immediately if you ingest any of this potion. The effects of the potion should not last more than four hours. If you have not used a Deflating Draught and are still swollen at that time, please consult with a healer.

Caution: Avoid exposure if pregnant, you have musculature problems, or if you suffer from a cardiac or pulmonary condition, as this may exacerbate the condition. Should you come in contact with the Swelling Solution and experience one of these conditions, please see a healer immediately for a dose of Deflating Draught and to verify no further harm was done through exposure. Children under the age of eight should never come in contact with the Swelling Solution. Side effects may include slightly increased heartbeat, lightheadedness, nausea and in some cases a low-grade fever.

Wisdom Served to Survive
Following the lesson, I thought it might be a good idea to explain why exposure to the Swelling Solution can be dangerous for those with coronary or pulmonary conditions. To start, it’s important to recognize the way in which the Swelling Solution works: it does not simply expand the particular body part being affected with air or extra tissue, but rather it impacts the body in the same way as when you are injured, such as when you twist your ankle climbing the castle stairs or fall on your wrist during a Quidditch match. Although you do not sustain a true injury that requires healing in any capacity, for a limited period of time, the potion prompts your body to behave as though it did.


Often when you get injured, such as in the ways mentioned above, you have probably noticed  localized swelling of the tissue around the injury, which is sometimes located near or around a joint (ankle, wrist, knee, and shoulder, for example). Most commonly this is an expression of a condition known as edema, in which the fluid collects in your bodily tissue. This increased level of fluid, naturally, causes that region to expand as blood and other bodily substances continue to flow into the area. A synthesized form of edema is what occurs when the Swelling Solution is used. Blood builds up in localized tissues with which the Swelling Solution came in contact for a temporary period of time. There is no pain and very little discomfort associated with it, but it is still not a very pleasant condition.

When the Swelling Solution is applied, the body typically builds up a rather large amount of fluid in the localized tissue, often more than during a typical injury, in fact. As a result, the body must work harder to ensure the rest of the body is receiving ample blood and other fluids even as so much is being held in the impacted tissue. The processes of the body, particularly the heart and pulmonary system, must work harder in order to continue overall functionality. This is why it’s particularly hazardous for those with heart conditions as well as certain lung conditions to be directly exposed to the Swelling Solution. This fluctuation in bodily systems can also be very hazardous for pregnant women as well.

Following this explanation of the effects of the potion on the regions of the skin that come in contact with it, it should be fairly obvious why ingesting the potion would be so hazardous. In fact, most commonly it leads to a full closure of the esophagus, and many poor witches and wizards have perished suffocating after accidentally swallowing some of the Swelling Solution. If you believe you may have swallowed any small amount, this is why it is vital that you seek medical help immediately. Even if your esophagus is somehow saved, it will then go into your stomach, and the digestive enzymes in your stomach have actually been found to speed and increase the reaction to this solution.

The Spots Get Smaller
In contrast to this potion, which is rather disruptive to the system, but relatively easy to brew, which is why it is so often used in the first few years of potions training, there is a slightly more complicated potion we mentioned called the Deflating Draught. This is something that would be useful to learn at some point, as it has the capacity to not only deflate areas of skin impacted by the Swelling Solution, but also bring down swelling in the event of an injury. The potion works by gently draining fluid that has accumulated in the tissues as well as preventing further fluid from being absorbed. This may occasionally create something of a blood rush, which leads to dizziness and loss of equilibrium. The body quickly regulates itself again, and the swelling and many of the dangers associated with it decrease.

In general, prolonged swelling over time can also cause damage to a person’s musculature, causing muscles to atrophy or waste away and diminish to some extent. This is typically owing primarily to the decreased use of that limb due to discomfort, pain, or difficulty of maneuvering. While the Swelling Solution does not yield effects that last long enough to cause this typically (and if it does, you should see a healer immediately), general swelling of this nature can and usually should be treated with a Deflating Draught.

Another use of the Deflating Draught is to help with blood clots. Sometimes swelling indicates the presence of a blood clot, which is formed when blood coagulates, or thickens and takes a solid or semi-solid form, and clogs arteries and veins. Swelling will not always be a definite sign of this, however, and other symptoms often include excessive warmth in the area as well as pain. This can lead to stroke, heart attack, and other potentially fatal consequences owing to these blocked systems of blood transport. However, the Deflating Draught, although not as effective as the Melting Serum, will often break up and push blood clots along.

In order to treat the blood clot in this way, the most expedient method of delivery is through a direct injection of the Deflating Draught into the affected vein or artery. Although most potions should not be injected directly into the bloodstream, there are rare ones that can help in circulatory issues. Please note that you should never inject any potion into yourself at home, and only certified healers should ever suggest injecting a potion. While topical contact or swallowing a particularly unsafe potion can cause serious harm, the dangers associated with injecting potions are even more severe.

Certain research-focused healers are actually looking into the Deflating Draught’s capacity to treat more serious maladies as well, such as brain swelling following traumatic head injuries. Similarly to your joints and tissues, your brain is capable of swelling for similar reasons following such an injury, as well as certain illnesses, strokes, and tumors. As one can expect, the swelling of the brain is an incredibly dangerous and occasionally fatal occurrence, and magical and non-magical beings alike are in grave danger when this happens.

Using the Deflating Draught in this capacity would involve neurosurgeons, or healers who specialize in brain, spinal cord, and other elements of the nervous system, being able to use the Draught in some capacity - either directly on the brain in an invasive topical form, or perhaps as a long injection into the brain itself even without surgery. This is still in the early stages of research, however, and does not have any conclusive data. It does, however, present an excellent example of a potion that was created specifically to target a certain problem - combating the occasionally more insidious effects of the Swelling Solution - that was found to have use beyond that narrow intent.

And this brings us to the final full lesson of the year. Next week will be your final, as well as your first Potioneer’s Log Check-In. Owing to that and all the preparations I expect you are currently doing, this week your assignment will consist solely of a simple quiz, in order to assess your understanding of today's material. 


Original lesson written by Professor Lucrezia Batyaeva
Image credits here, here, and here

In Year Two, Potions students will delve more deeply into potioneering, theory, and will explore in greater detail how certain potions can impact a witch or wizard's biological processes.
Course Prerequisites:
  • PTNS-101

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