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What is Potassium Chloride?


Potassium chloride is a naturally occurring compound made up of potassium and chlorine, and has the chemical formula KCl. This compound is used heavily in agriculture, is a component of some medications, and has a number of household uses. KCl has many of the same properties as regular table salt (NaCl): both are crystalline in form, dissolve easily, and can be absorbed by humans and plants. The two compounds are also halide salts, which refers to the presence of the element chlorine and gives them certain electrochemical properties. In chemical makeup and uses, however, the two salts are quite different.

Agricultural Uses

Potassium chloride.
Potassium chloride.

The most common place to find potassium chloride is on a plant fertilizer ingredient list. This mineral is essential to organic growth, and both humans and plants depend on it for survival. While humans typically get all they need through food, plants, depending on the quality of the soil they are planted in, may not. Farmers often choose fertilizers enriched with potassium compounds in order to boost crop growth.

Potatoes are a natural source of dietary potassium.
Potatoes are a natural source of dietary potassium.

Potassium in chloride form is often the best vehicle to deliver this needed mineral. It is inexpensive, for one thing, and is also very easily absorbed by soil and plant roots. Other potassium compounds often take longer to break down, which can delay their effects.

Soil that is rich in potassium often yields fuller, richer crops. Plants exposed to the mineral grow bigger, brighter leaves and often produce more fruit. The science of adding this mineral is an exact one, though, and too much can be damaging to plants. Most commercial fertilizers have been analyzed and balanced by professionals to ensure that they contain only precise amounts of potassium and other minerals.

Dietary Deficiencies

Farmers often choose fertilizers enriched with potassium compounds in order to boost crop growth.
Farmers often choose fertilizers enriched with potassium compounds in order to boost crop growth.

While most people get all the potassium they need through the foods they eat — fruits, vegetables, and meats are all good sources — not everyone does. People who suffer from deficiency, which is known as hypokalemia, may need to supplement their intake in pill form. The chloride compound is usually a better choice than straight potassium or other compounds in medication because of how easily and quickly it can be absorbed. Drugs and supplements containing this mineral are sold under many trade names, but usually list potassium chloride with the other active ingredients.

Consuming foods which contain potassium can lessen the effects of sodium on blood pressure.
Consuming foods which contain potassium can lessen the effects of sodium on blood pressure.

Hypokalemia is a serious condition. Not only is potassium essential to regular growth and functioning, it also plays a crucial role in keeping the heart beating. People with deficiencies often have weak or irregular heartbeats, which can be life threatening. They may also be chronically dehydrated. Slowly reintroducing the potassium chloride into the body helps boost electrolyte levels, which can prevent and treat dehydration caused by illness, excessive exercise, or intoxication.

Replacing Salt

Taking too many potassium pills may result in severe sickness.
Taking too many potassium pills may result in severe sickness.

Potassium chloride is often included in salt substitutes because of how much it resembles salt. The two substances taste similar, but potassium chloride crystals are often a bit bitter, and may do less to heighten or enhance the flavor of foods the way salt does. For this reason, it's usually only one of several ingredients in substitute products.


Most people don't need to take supplements that include this compound unless directed by a health care professional. People with hypokalemia almost always know that they are sick, and the risk of potassium deficiency among healthy people is relatively small. While getting a bit extra is rarely dangerous, people with certain medical conditions can be harmed by excessive quantities of this mineral.

Kidney disease sufferers in particular are usually advised to avoid supplemental potassium. When the kidneys are weak, they cannot process minerals as efficiently as they should, which can cause them to build up in the blood. The condition is known as hyperkalemia and is often just as serious as a deficiency.

Possibility of Overdose

It is not usually possible to overdose on naturally occurring potassium, as it exists in only small concentrations in most foods. In pill form, however, overdose can be a serious concern. While not getting enough potassium can slow a person's heartbeat, too much often stops it outright.

Potassium chloride is one of several drugs used in lethal injections — including executions and euthanasia. When injected it helps cause the heart to stop beating (cardiac arrest). Concentrated injections of the compound are almost always deadly. Taking too many potassium pills can also lead to death, but most of the time, a person will get very sick first, often experiencing irregular heart rhythms.

As a Water Softener

Many home improvement and pool supply stores sell loose potassium chloride salts for use in water softening systems. The idea of soft or hard water can sometimes be confusing, as it relates to mineral content rather than actual texture. Hard water is water that has a high mineral content. The precise makeup of hard water can vary, but calcium carbonate and magnesium are almost always present. Lime scale or calcium buildup in appliances is often caused by hard water.

When hard water is filtered through a trap containing potassium in chloride form, the chlorine ions bond to the minerals in the water and a chemical reaction happens. As a result, potassium ions enter the water, and corrosive elements like calcium chloride and magnesium remain trapped in the filter. Only very low concentrations of potassium are added to the filtered water.

Industrial Uses

When combined with other positive ions, particularly lithium, zinc, and ammonia, potassium chloride can be very helpful in calibrating molecule scales and other precise scientific equipment. It is especially useful in radiation monitoring equipment. When exposed to high temperatures, potassium produces beta radiation and serves as an optical crystal, or prism, that can help scientists assess transmission precision.

Common batteries may also contain potassium chloride. The compound serves as a bridge between copper sulfate and zinc sulfate, which enables the flow of electrons between the electrodes.

In some places, the chloride compound may also be used as an "environmentally friendly" way of melting ice. It is usually as effective as salt, but does not leave behind any residue. Excess potassium is usually absorbed by nearby plants once the ice melts.

Early fire extinguishers contained potassium chloride, as the compound can be effective at smothering flames. Advances in the fire fighting field have turned up a number of more efficient compounds for this purpose, however. Still, in major disasters such as wildfires, the chloride compound may still be used — but usually in later phases, as the blazes begin to subside.

Discussion Comments


Please help! Can potassium intravenous infusions stop the heartbeat of a baby at 10 weeks? Mine died two days after I had the potassium infusion.

Thank you!



@anon22150: Keep visiting doctors until you find good professional help. Best of wishes for your health!


A fetus has a heart beat just days after conception. If it has a heartbeat (thus a brain, and limbs), it is a baby.


#8: How something is worded in a clinical setting is considerably different than is casual settings. A fetus is a fetus. It is not a 'baby' until it is born. Period.


"Used to stop the heart of the fetus after delivery." Interesting word choice. It sort of sanitizes the ghastly reality of the procedure. What you really mean, but won't say, is, "used to stop the heart of the baby after delivery." Or "used to kill the baby after delivery."


In regards to your advice about waiting between filling removal to give your body time to remove the toxins"

I understand that mercury is one of the toxins that cannot be processed and removed by the body's natural functions that would normally self cleanse.

"Fun" fact: Mercury is the second most toxic substance to the human body. The first is radioactive material.


to anon 24331 regarding your aunt. I believe what may have happened is this:

You were correct to have the fillings removed. However, they do not tell you that removing these fillings releases the mercury. imagine the pieces, even tiny ones, that fall into the mouth, as the filling is being drilled out.

I had this done. I went to a good doctor and he put a huge plastic protective liner in my mouth as he took them out, but still i felt some filling material in my mouth and i was concerned. i let him take out maybe three, then i found out taking them out can cause a huge influx of mercury to be released, even through the skin of the mouth.

I stopped as i felt worse after three were taken out. i got really sick afterwards. I think the doctor should have also put me on a metal detox either before or after, or during. At any rate, i also got very ill. (they called it chronic fatigue). i was younger then and fought it. Sadly, this will not bring your aunt back! so sorry!

however, this info may help you understand, and if you are angry you might talk to this dentist. They should not be just removing fillings. i hope it at least helps to understand what i believe happened.

Also a warning to others: be wary. Look into metal detox before having them taken out and do one at a time, and take a break to give your body time to release the toxins and to recover. Don't let the doctors set you up for a big schedule of removing those fillings. I believe this is close to malpractice, so just say no. Have one at a time done and wait about two months before the others. Bless!


We have an aunt who just passed away and Dr. said she too had high amount of mercury in her system. So they took her to Dentist to have all silver fillings replaced. Still no change. She had seizures, couldn't think clear, couldn't remember, got real skinny, diarrhea, vomiting all the time, shakes,....Dr.'s thought it was then Neurological and deemed to be Creujzfeldt jakob disease. She passed away (I won't give details on what we actually think happened) autopsy was done and it was NOT Creujzfeldt Jakob disease. Husband cremated her and now we will never know.....


Help, To whom it may concern: I had been threatened by my ex-boyfriend 2003-2005 that he had a chemical that is undetectable in human body that will kill me slowly eventually...I had swelling in my skin, mucous coming out of my breasts and I had unusually bleeding numbness in my extremities...All in all the Dr. at St. Joseph's Hospital in Orange County wrote me up as 51-50 and I've silently suffered, since and haven't looked into it again. I still feel I am physically having side effects. My Doctor tested me for metals and found I have a high amount of Mercury in my body. He said out of all the 25 years in practice he has never seen such high amount in anyone's Body. Today, I tell a friend of a friend who looks on the Internet and finds Potassium Chloride poisoning as the same type symptoms I've been struggling with for the past few years. Help...I think she found that I have been struggling with paresthesia.

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