D-phenylalanine is not an essential amino acid. Its role in the body is not currently understood. L-phenylalanine is an essential amino acid. It is the only form of phenylalanine found in proteins. Major dietary sources of L-phenylalanine include meat, fish, eggs, cheese, and milk.
Phenylalanine is most commonly used for a skin disorder that causes white patches to develop on the skin (vitiligo). It is also used for aging skin, pain, obesity, and many other conditions, but there is no good scientific evidence to support these uses.
How does it work ?
Uses & Effectiveness ?
Possibly Effective for
Possibly Ineffective for
- Attention deficit-hyperactivity disorder (ADHD). Some research suggests that patients with ADHD have lower levels of amino acids such as phenylalanine, so there was hope that providing phenylalanine might treat ADHD. However, taking phenylalanine by mouth does not seem to have any effect on ADHD symptoms.
- Chronic pain. Taking D-phenylalanine by mouth does not seem to reduce pain.
Insufficient Evidence for
- Aging skin. Early research shows that applying a modified form of phenylalanine called undecylenoyl phenylalanine as a 2% cream twice daily for 12 weeks can reduce the number of age spots.
- Depression. Limited clinical research performed in the 1970s and 1980s suggests L-phenylalanine or DL-phenylalanine might be useful for depression. However, this research needs to be confirmed. Taking D-phenylalanine does not appear to improve symptoms of depression.
- Obesity. Early research shows that L-phenylalanine does not reduce hunger in people who are obese or overweight.
- Parkinson disease. Limited research suggests taking D-phenylalanine might decrease symptoms of Parkinson disease.
- Acute pain.
- Multiple sclerosis (MS).
- Other conditions.
When applied to the skin: L-phenylalanine is POSSIBLY SAFE when applied as a cream, short-term.
Special Precautions and Warnings
While breast-feeding, Phenylalanine it is LIKELY SAFE for breast-feeding mothers whose bodies' process phenylalanine normally to consume the amount of L-phenylalanine found in food. However, do not take more.But there isn't enough reliable information to know ifNot enough is known about the safety of taking L-phenylalanine is safe to use in medicinallarger amounts duringwhen breast-feeding.
There isn't enough reliable information to know if D-phenylalanine is safe to use when pregnant or breastfeeding. Stay on the safe side and avoid use.
Phenylketonuria (PKU) and other conditions that cause high levels of phenylalanine: Phenylalanine should be avoided in people with certain inherited disorders that cause their bodies to build up too much phenylalanine. Phenylketonuria (PKU) is one of these diseases. People with this disorder can develop mental retardation, high blood pressure, stroke, and many other serious health issues if they consume phenylalanine. PKU is so serious that babies are screened at birth to determine whether they have the disorder and will need a special diet to avoid these problems.
Schizophrenia: Use with caution. Phenylalanine can make a movement disorder (tardive dyskinesia) in people with schizophrenia worse.
Levodopa interacts with PHENYLALANINE
Levodopa is used for Parkinson's disease. Taking phenylalanine along with levodopa can make Parkinson's disease worse. Do not take phenylalanine if you are taking levodopa.
Do not take this combination
Medications for depression (MAOIs) interacts with PHENYLALANINE
Phenylalanine can increase a chemical in the body called tyramine. Large amounts of tyramine can cause high blood pressure. But the body naturally breaks down tyramine to get rid of it. This usually prevents the tyramine from causing high blood pressure. Some medications used for depression stop the body from breaking down tyramine. This can cause there to be too much tyramine and lead to dangerously high blood pressure.
Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.
Medications for mental conditions (Antipsychotic drugs) interacts with PHENYLALANINE
Some medications for mental conditions might cause jerky muscle movements. Taking phenylalanine along with some medications for mental conditions might increase the risk of jerky muscle movements.
Some medications for mental conditions include chlorpromazine (Thorazine), clozapine (Clozaril), fluphenazine (Prolixin), haloperidol (Haldol), olanzapine (Zyprexa), perphenazine (Trilafon), prochlorperazine (Compazine), quetiapine (Seroquel), risperidone (Risperdal), thioridazine (Mellaril), thiothixene (Navane), and others.
Be cautious with this combination
- A skin disorder that causes white patches to develop on the skin (vitiligo): 50-100 mg/kg of L-phenylalanine once per day has been used. L-phenylalanine 50 mg/kg three times per week for up to 3 months has also been used.
- A skin disorder that causes white patches to develop on the skin (vitiligo): Applying a 10% phenylalanine cream to the skin has been used.
- A skin disorder that causes white patches to develop on the skin (vitiligo): Phenylalanine 100 mg/kg twice weekly for 3-4 months has been used.
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