L-Citrulline is a basic amino acid which the body uses to form proteins. Its chemical composition is H2NC(O)NH(CH2)3CH(NH2)CO2H and it is abundantly found in watermelon.
When consumed, the compound transforms into several other key aminos, which increase blood flow to the brain.
In addition to boosting circulation, L-Citruline can improve energy and alleviate symptoms of fatigue.
It is also used to treat a variety of ailments, from erectile dysfunction to Alzheimer’s disease. The following is an overview of how the compound works and the mental benefits it produces.
While Citrulline has few known side effects, its byproduct L-Arginine does exhibit some risks, which will be detailed below.



- Shown to raise blood arginine levels
- Increases Nitric Oxide & Growth Hormone
- Delays onset of fatigue during intense training
Citrulline Effects
Related Topics
- L-Citrulline
- Citrulline Malate
- L-Citrulline Supplements
- L-Citrulline Benefits
- Citrulline Malate Effects
- L-Citrulline Dosages
- Citrulline Malate Dosages
- L-Citrulline Foods
- Potential Side Effects
- Citrulline for Bodybuilding
- L-Citrulline for Depression
- Citrulline Malate Reviews
- Primaforce Citrulline Malate
- L-Arginine vs. L-Citrulline
When it is consumed, Citrulline becomes the pre-cursor to L-Arginine.
This compound is well-known for its supportive role in circulation and heart health. It cuts blood pressure by dilating blood vessels, assisting in removing any blockages.
This circulation effect impacts systems throughout the body, including sexual health, the healing of wounds, and pain due to inflammation. It also increases the amount of growth hormone in the body.
Citrulline also gets converted into nitric acid. This compound further enhances blood flow through arteries. In the brain, all of these functions help support healthy neural function, particularly as it pertains to memory.
The increased circulation in the brain delivers blood and nutrients to neural tissue, keeping it limber and encouraging rapid growth of neural structures like synapses and neurons. This is similar to the neural circulation effects which are caused by the natural herbal supplement Vinpocetine.
Citrulline Benefits
Citrulline promotes blood circulation and the release of human growth hormone. This can increase resistance to injury and illness. The supplement supports high functioning immunity in all systems of the body. It speeds recovery from cuts and surgeries. It also contributes to bone strength.
L-Citruline is an excellent therapy for high blood pressure. For mens’ sexual health, the compound is thought to have similar effects of prescription drug Viagra. In the brain, more circulation and oxygen results in sharper, clearer thoughts.
Short term memory, long term memory, and recall are all enhanced. It has been suggested as a natural treatment for Parkinson’s Disease, as it may help those patients achieve a higher degree of mental control.
Citrulline Dosage
As this dietary supplement is still not widely used by the general public, there are few published papers detailing appropriate doses. There appears to be a wide range of effective dosages, from 2 grams to 15 grams per day. A median dose of 6 grams is recommended for use in weight loss and exercise programs.
Citrulline appears in this market even more frequently than as a holistic cognitive enhancer, as its circulation effects increase metabolism surrounding heavy exercise. If you are unsure about dosage, start with a very small amount, perhaps closer to 1 gram per day, and note effects before increasing the dosage.
Citrulline Side Effects
Citrulline is considered very safe, and has no known side effects.
It is important, however, not to combine it with prescription medications for high blood pressure. Adding this supplement may reduce blood pressure to dangerous levels as a result.
Also, any use of erectile dysfunction medications such as Viagra or Cialis should be suspended while taking Citrulline. Again, low blood pressure may result. Pregnant or breastfeeding women are advised not to take it at all.
There was an FDA recall in 2014 over several shipments of the drug. This was not due to an inherent danger in the compound itself, but was related to incorrectly packaged and labeled supplements. No one was harmed due to the error, and Citrulline is still considered safe for use by adults and children.
L-Arginine (the amino acid synthesized from L-Citrulline) does have some noted side effects when it is taken as a standalone supplement. For some people, too large of an arginine dose can result in digestive issues like diarrhea and abdominal pain. It can also add to allergic sensitivities, and activate asthma attacks. Argnine does possess the same contraindications for blood pressure as listed above.
Citrulline Review
Citrulline is a natural amino acid which is converted by the body into L-Argnine and nitric acid. These compounds both work to increase circulation throughout the entire body, including the brain. This effect may generate increased immunity, more energy, and better heart function. It also contributes to strong neurological tissue, with excellent memory and concentration effects. It has no known side effects and is safe for use by children.
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Article last updated on: April 29th, 2018 by Nootriment