ALCAR side effects are rare, mild, and generally do not take away from any of the positive benefits of the supplement.
This is to be expected since the compound is produced within the human body and exists in almost every one of your cells in some form or another.
Adding supplemental sources of the amino acid Acetyl L-Carnitine to your diet is unlikely to cause problems, but it is important to be aware of the possible side effects before using it.
This article will address the safe usage of ALCAR powder or capsules and help to explain how this natural substance works.



- Increases mental energy & focus
- Promotes neuron health & anti-aging
- Improves memory, alertness & signalling
What is ALCAR’s Role in the Body?
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ALCAR is one of the natural forms of the amino acid L-Carnitine, responsible for transferring fatty acids into the mitochondria.
These fat sources can clog up arteries without Carnitines available to help transport them.
Using an ALCAR supplement can increase the rate at which fatty acids are supplied to your cells, leading to increased energy production for both mental and physical activities.
As a result, the main reason people take Acetyl L-Carnitine is to boost energy levels and promote weight loss.
There are many additional benefits related to the brain, memory, concentration, and mood, as well as longevity of life.
What makes ALCAR special among different forms of L-Carnitine is that it has the ability to cross over the Blood Brain Barrier, otherwise known as the BBB.
Many of the ingredients found in dietary supplements today cannot penetrate this filtration system that protects brain tissues from the circulating blood flow. This means they are incapable of enacting real changes to mental performance and brain health.
N-Acetyl L-Carnitine is different because its acetylated form acts as a carrier so that it can cross the blood-brain barrier.
Benefits and Uses
Because it can cross the blood-brain barrier, ALCAR can act as an antioxidant within the brain. It has been used at hostpitals in treating multiple injuries, including those in the spinal cord and peripheral nerves. More research has yet to be done, but ALCAR may also have a neuroprotective benefit while treating Parkinson’s Disease.
Other uses include for nerve pain, obesity, heart problems, and anxiety. In research studies, ALCAR has even been seen to improve the severely impaired memory function seen in alcoholics.
Some patients with depression use ALCAR to ameliorate their symptoms in a mostly side-effect free manner compared to other antidepressant medications. Not only can it help to restore neurochemical balance in the brain, it provides patients with heightened energy levels which may help with the feelings of fatigue that often accompany depressive episodes.
This nootropic supplement has also been used in diabetes patients who suffer from muscle pain and discomfort, as well as peripheral neuropathy.
Since ALCAR takes fatty acids that clog the body and turn them into energy, it theoretically may assist with weight loss.
ALCAR reduces systolic blood pressure and strengthens the blood vessels to increase circulation. This can result in improved oxygenation of organs like the brain as well as better waste removal of any toxins or damaged cells.
Some studies have shown that sperm motility can also be increased and males who struggle with infertility have used the supplement to boost their T-cell count.
The Natural Medicines database has rated ALCAR as Possibly Effective for Alzheimer’s disease, age related cognitive impairment, general cognitive impairment, diabetic neuropathy, male infertility, and chronic cerebral ischemia. The research on the benefits of ALCAR are very promising, however more research still needs to be done. At this time, Acetyl L-Carnitine is only sold as a health supplement in the USA, and the FDA has not approved ALCAR as a drug to prevent or treat any conditions.
ALCAR Side Effects and Contraindications
ALCAR has been rated by the Natural Medicines database as Likely Safe when used orally and appropriately. ALCAR has been used safely in clinical trials lasting up to 33 months. In general, ALCAR side effects are rare and serious adverse effects are almost non-existent for healthy adults.
Although side effects are minimal and rare, an overdose in ALCAR can increase the intensity of any negative effects.
ALCAR carries a low toxicity, so taking the recommended amount will not result in severe consequences.
However, some mild discomfort may be experienced by certain users.
The side effects that have been found with ALCAR include:
- Nausea
- Abdominal cramps
- Headache
- Vomiting
- Interference with metabolism in the thyroid
- Increase in seizures for those that have epilepsy
- Fishy odor found in breath or urine
Alzheimer’s disease patients that suffer from ALCAR side effects due to excessively large dosages may experience some psychiatric disturbances. These can include depression or confusion, but it is hard to determine if these are truly ALCAR side effects, or a result from Alzheimer’s itself.
Although the supplement provides many positive effects for the average user, there are certain people who should steer clear of the medication. Those that suffer from insomnia should not use ALCAR because the increased energy it brings may lead to difficulties in falling asleep.
Women who are pregnant or nursing should not take ALCAR as there have been no clinical trials conducted so far to determine the effects of this supplement on the developing baby.
Some hyperactive individuals may find that using this nootropic leads to an over-abundance of energy. Individuals with ADHD often see improvements to attentional control with ALCAR dosages, but this is something you should speak to your doctor about before deciding to use this supplement.
Patients who have an under-active thyroid should not take ALCAR as it could react negatively with the thyroid hormone and cause distress and discomfort.
What is the Best ALCAR Dosage
Proper dosage is dependent on many factors including age, weight, physiology, and personal sensitivities. The below recommendations are general guidelines only, and your personal dosage could be different. It is always recommended that you speak with your doctor to determine the best dosage for your needs.
Since ALCAR is a supplement that is water soluble, professionals have suggested that it be ingested orally with the aid of food. The average sized adult is suggested to take a dose of 500 to 1000 mg, while some have found success with 1500 mg with minimal side effects.
Keeping your dosage to this minimum amount can help prevent most, of the side effects found with ALCAR. Dosage can be modified to meet specific personal needs, but taking more than 1g of ALCAR can increase the chance of seeing side effects increase considerably.
Stacking ALCAR with Citicoline and Alpha GPC can also increase the chance of side effects such as headaches. However, some users find the benefits of this supplement for memory and energy to be greatly increased when using these supplements together.
This may be a matter of personal sensitivity and you might want to experiment to determine whether this stack works for you or not.
Given the minimal risk of ALCAR side effects for most individuals and the many positive benefits, this may be a smart supplement to add to your daily stack.
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Article last updated on: April 25th, 2018 by Nootriment