Added to Cart
Cart Total:
Customers Also Bought:
24/7 Help

1-9 of 9 total
Sort By
Search Reviews

Perfect for people with genetic problems

Posted by iHerb Customer on Oct 08, 2012 | Verified Purchase

I've just discovered I have a rare inborn error of metabolism that leads to low levels of tetrahydrobiopterin (BH4). I tried ordinary L-tyrosine and it worked. Norival actually includes biopterin (although doesn't state which form BH4 or BH2)and cofactor P5P, in addition to N-acetyl L-tyrosine (active form). A deficiency of an enzyme is felt in every cell, especially in the brain. Norival made my brain work properly, my temperature regulation improved amazingly! The dose must be individually adjusted. I take all such supplements 3x daily, in smaller doses, to keep the blood supply stable. I only wish I could contact the company, to learn which biopterin they use.

Thanks for your feedback!

Norival, 120 capsules

Posted by iHerb Customer on Oct 18, 2011 | Verified Purchase

This product works well with L-Methylfolate (5-MTHF). For those with homozygous MTHFR 677C-T mutation Norival and L-Methylfolate 10mg has helped my mental clarity, lethargy, moodiness, and depressive episodes. I am not on any antidepressants. Has also worked well for my teenage son with the same double MTHFR mutation.

Thanks for your feedback!

Terrific for restless leg syndrome, insomnia, ADD!

Posted by iHerb Customer on Apr 17, 2011 | Verified Purchase

Restless leg syndrome is a dopamine deficiency like Parkinson ’s disease or Attention Deficit Disorder. Tyrosine is the amino acid necessary for dopamine production. Tyrosine requires B-12, folinic (folic) acid and B-6. Many of us do not properly metabolize standard folic acid, requiring an alternative form called Biopterine (BH4). Plain tyrosine gave me terrible diarrhea, even when taken with B-complex. This is the only tyrosine combination I can take without negative side effects. Taken 2 hrs before bedtime helps with the restless leg insomnia, or when I get the shakes, or early in the morning when I just can’t get going, really works. Love this product!

Thanks for your feedback!


Posted by iHerb Customer on Dec 16, 2010 | Verified Purchase

Tyrosine helps with the production of dopamine which is lacking in people with Parkinson's. Some people like myself have a hard time assimilating tyrosine without it's co-factor biopterin. Norival has both N Acetyl L Tyrosine and Biopterin. It has been of great help in reducing my symptoms.

Thanks for your feedback!

There are better options if not looking for the rare Biopterin

Posted by iHerb Customer on Jun 07, 2013 | Verified Purchase

I get a nice awakening push from plain Tyrosine, however, far from improving mood I get irritable on this product.

Thanks for your feedback!

Did not experience benefits noted by others

Posted by Health-Is-Wealth on Oct 30, 2013 | Verified Purchase

Nice idea, but these don't work for me - P5P causes me to feel rubbish. I'd maybe get this again to try it if it contained non-P5P B6, non-acetyl tyrosine and biopterin - and if it didn't contain added stearate and sillycon. I recently tried Jarrows acetyl tyrosine with B6 - beneficial only for the small amount of B6, but I know that L tyrosine works. If this review was helpful to you, please click YES below - thank you. For reviews of all the products I have purchased from iHerb, please click my username above.

Thanks for your feedback!


Posted by iHerb Customer on May 24, 2011 | Verified Purchase

I've used this product for years. I believe it has truly made a difference in my overall mood, which has greatly improved. Feed your body with what it needs and it will work for you.

Thanks for your feedback!

Trying these for restless legs.

Posted by iHerb Customer on Jun 30, 2011 | Verified Purchase

I bought these, along with Natural Factors E400IU Succinate, after a search for products that might help restless legs, which I've had, off and on, most of my life. It's the first time I've ever taken anything for the problem, as it comes and goes, but the latest bout spurrd me on. I opted to take them in the morning, not at night. I can't say yet if these products work for sure, but I haven't had any problems since my last bout a few days after I started taking both supplements.

Thanks for your feedback!

Wait and see

Posted by iHerb Customer on Jun 20, 2011 | Verified Purchase

We just started this product and my twelve year old daughter is taking this product. It is easy to swallow and digest. It was hard to find this product in the local stores so we were thrilled to see it at iherb.

Thanks for your feedback!

1-9 of 9 total