NAC (N-Acetyl Cysteine) Supplements Review
Choose the Best N-Acetyl
Cysteine Supplement. See Our Tests of Popular NAC Supplements and Top
Picks for Quality and Value.
Medically reviewed and
edited by Tod Cooperman, M.D. 
Last Updated
: 09/24/2021 | Initially Posted:
02/15/2019Latest Update: Why NAC Is Coming Off Retail Shelves
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Table of Contents
Summary
·
What is it? NAC is a synthetic compound that is converted to
glutathione in the body (see What It Is).
·
Does it work? NAC has a wide variety of uses —
although not all are well-proven. As a prescription drug it is used to treat acetaminophen
poisoning (to protect the liver), but general claims of "liver
protection" are not well established. It has also been used in inhaled
form to loosen mucus in people with cystic fibrosis, and orally it may help
with symptoms of flu, chronic bronchitis and COPD symptoms, but evidence is
weak for its purported ability to thin mucus during a cold
and general claims of "immune support." (See What It Does).
·
What did CL find? ConsumerLab
found the cost to obtain 600 mg of NAC ranged over 15-fold from
just 4 cents to as much as 63 cents. A single dose of NAC ranged from 500 to
1,000 mg. Quality-wise, all products contained their claimed amounts of NAC,
although one also contained a significant amount of sodium. (See What CL Found and use the Results table to compare the amounts of
NAC and sodium in products).
·
Top Picks — ConsumerLab selected Top Picks for
NAC as a powder, capsule, and tablet based on quality, value, and other
features.
·
What to look for? NAC is always in the "free
form" so if you see this on a label, it's nothing you should pay more for.
Just choose a product that provides the dose you want at a low cost --
generally 4 to 15 cents per 600 mg. (See ConsumerTips™).
·
How much to take and when? The dose of NAC used in clinical trials
has ranged from about 600 mg to 3,000 mg per day, typically divided into two or
three servings. See the What It Does section for the dosage for
specific uses.
·
Why are some retailers no longer selling NAC? The FDA made it
clear in 2020 that it considers NAC to be a drug and not a dietary supplement,
so, for legal reasons, some companies have stopped selling it (See ConsumerTips™ for
details).
·
Cautions: NAC can cause headache and gastrointestinal side effects.
It can also worsen asthma. For details, see Concerns and Cautions.
What It Is:
NAC
(N-acetyl cysteine), which is also known as just acetylcysteine, is a synthetically
modified form of the amino acid cysteine (cysteine occurs naturally in foods,
whereas NAC does not). In the body, NAC is converted to the antioxidant
glutathione. NAC is not an essential nutrient and there is no recommended daily
allowance.
What It Does:
N-acetyl cysteine is available as a dietary supplement (taken
orally) as well as a prescription medication. As a prescription medication, NAC
in solution is given orally or intravenously to treat acetaminophen
(Tylenol®) poisoning, as it helps replenish glutathione in the liver which
is depleted by high doses of acetaminophen). Preliminary studies in animals
suggest that when taken with large doses of acetaminophen, NAC
may help protect the liver from acetaminophen-induced liver damage, and may even
increase the anti-inflammatory effects of acetaminophen (Owumi Drug Dev Res
2015; Qiu Vet Immunol Immunopathol 2013), but no human studies have
evaluated this. A small study in people with advanced cancer suggests that
intravenous NAC taken within 8 hours after very high doses
acetaminophen seemed to protect the liver (Kobrinsky, Cancer
Invest 1996). NOTE: NAC is often promoted as supporting the
liver, likely based on its effect in acetaminophen poisoning. However, a
general liver-protectant effect has not been established.
NAC has been used in combination with nitroglycerine, to treat angina,
but results have been mixed.
An inhaled aerosolized NAC solution ("a mist") is also used to help
loosen and clear mucus in the airways of patients with cystic fibrosis.
(Note: These conditions should be treated only under medical supervision; do
not attempt to treat with oral NAC supplements).
One placebo-controlled clinical study found 600 mg of NAC taken
twice daily during flu season (October — April) did not prevent infection but
significantly reduced flu symptoms in people who contracted
the flu virus (De Flora, Eur Respir J 1997).
Among individuals taking NAC who became infected, only 25% became symptomatic,
versus 79% in the placebo group. There is some preliminary evidence that NAC
supplementation may improve certain blood markers of immune system
function. For example, a small study among postmenopausal women in Brazil
found that 600 mg of NAC (taken as an effervescent tablet dissolved in half a
glass of water) daily at bedtime for four months increased natural killer cell
activity and improved other measures of immune system function compared to
before supplementation. However, the study was not placebo-controlled and did not
report the occurrence of illness (colds, flus, etc.) (Arranz, Free Radic Biol Med 2008). NAC supplementation
has also been reported to restore natural killer cell activity in individuals
with HIV (Droge, Proc Nutr Soc 2000). However, there is not sufficient
evidence to suggest that NAC supplementation "boosts" the immune
system to the extent that it will reduce the occurrence of illness.
NAC may decrease the frequency of flare-ups of chronic
bronchitis and COPD (chronic obstructive pulmonary
disease). An analysis of eight clinical trials found that 400 mg to 600 mg of
NAC taken daily for 3 to 6 months significantly reduced exacerbations of
chronic bronchitis (Grandjean, Clin Ther 2000).
In another clinical study, COPD patients who received 600 mg of NAC in addition
to standard treatment medications daily for six months had significantly fewer
flare-ups than those who received only medication (Pela, Respiration 1999).
Because of its mucus-thinning properties, NAC is
sometimes promoted for clearing nasal congestion due to colds
or sinusitis. NAC has been shown in laboratory studies to thin nasal mucus when
applied directly to mucus samples (Rhee, Arch Otolaryngol
Head Neck Surg 1999) and to increase nasal flow when inhaled in
combination with a decongestant (Cogo, Arzneimittelforschung 1996). However, there is little
clinical evidence that oral supplementation reduces the amount or thickness of
nasal mucus: A preliminary study in Iran suggested
a beneficial effect but, strangely, lacked details about dosage, and a study to have been conducted in Canada was
either not completed or not published.
There is no evidence showing that NAC supplementation
can prevent COVID-19. However, a study in Greece among
82 adults (average age 63) hospitalized with moderate or severe COVID-19
pneumonia found that, compared to standard treatment alone, 600 mg of
NAC (as granules dissolved in half a glass of water) given twice daily in
addition to standard care for 14 days or until hospital discharge,
significantly decreased rates of progression to severe respiratory failure
(with need for mechanical ventilation). NAC treatment also significantly decreased
mortality at 14 and 28 days after hospital admission. Two of the 42 patients
(4.7%) who were given NAC required mechanical ventilation within 14 days of
hospital admission, compared to 12 of the 40 (30%) patients who received only
standard care. Similarly, at 28 days, 2 patients (4.7%) who received NAC in
addition to standard care died compared to 12 of the patients (30%) who
received standard care alone (Assimakopoulos, Infect
Dis (Lond) 2021).
In women being treated for infertility associated with polycystic
ovarian syndrome, taking 1,200 mg NAC daily along with the fertility drug
clomiphene citrate was shown to significantly increase rates of ovulation and
pregnancy compared to treatment with clomiphene citrate alone (Rizk,
Fertil Steril
2005).
A small double-blind clinical trial in people with Sjogren's syndrome found
that 200 mg of NAC taken 3 times per day improved eye-related symptoms such as
eye soreness and irritation, (Walters, Scand J Rheumatol Suppl 1986).
A study in Iran among 168 people (average age 39)
with ulcerative colitis in remission maintained with
prednisolone (a corticosteroid) and mesalamine (an anti-inflammatory agent)
found that taking 400 mg of NAC twice daily for 16 weeks while slowly
discontinuing prednisolone helped maintain remission by week 22 compared to placebo.
The relapse-free period was about 1.5 weeks longer for people given NAC
compared to those given placebo (21.12 vs. 19.55 weeks), and relapse occurred
in only 7% of people in the NAC group compared to 22% of people in the placebo
group (Shirazi, Clin Res Hepatol
Gastroenterol 2020).
In patients with end-stage renal failure, 600 mg
of NAC twice daily reduced the incidence of cardiovascular events, including stroke
and heart attack, by 40% compared to placebo, although it did not reduce
overall mortality (Tepel, Circulation
2003). NAC (also called acetylcysteine) has been used to
prevent kidney injury in patients undergoing angiography (imaging of blood
vessels); however, a large study found that giving 1,200 mg of NAC one hour
before and after angiography and twice daily on the following four days
provided no benefit compared to placebo (Weisbord, NEJM 2017)
NAC has been found to lower homocysteine levels. High levels of
homocysteine are associated with a higher risk of heart disease, although it is
not necessarily a causative factor. In a small clinical study, effervescent
tablets containing 2,000 mg of NAC dissolved in water and taken twice daily for
two weeks lowered homocysteine levels by 45% compared to placebo (Wiklund, Atherosclerosis 1996).
There is some evidence that NAC may help reduce the
severity of symptoms in certain mental health disorders. One randomized,
double-blind clinical trial in people with schizophrenia found
1, 000 mg of NAC taken twice daily in addition to maintenance medications
significantly improved scores on symptom scales and decreased restlessness
compared to the medications plus placebo (Berk, Biol Psychiatry 2008). A more recent
study of patients with chronic schizophrenia taking risperidone found that NAC
supplementation (up to 2,000 mg per day) resulted in significantly improved
scores on tests of negative symptoms compared to risperidone plus a placebo (Farokhnia, Clin Neuropharmacol
2013).
Several small but well-controlled clinical studies (all
by the same lead researcher) indicate NAC may also be helpful in reducing compulsive
behavior -- possibly by affecting glutamate concentrations in the
nucleus accumbens of the brain. In a study involving
adults with excoriation (skin picking) disorder, 1,200 to 3,000 mg
of NAC per day or placebo was taken for 12 weeks (the dose increased to 2,400
mg at week 3 and to 3,000 mg at week 6) along with existing medications.
Compared to placebo, NAC treatment was associated with significant
improvements: 47% of the NAC group was "much or very much" improved
versus 19% of the placebo group, and scores on an obsessive-compulsive
excoriation scale decreased from 18.9 to 11.5 in the NAC group, versus 17.9 to
14.1 in the placebo group. However, quality of life scores did not change
significantly for either group. The researchers concluded that benefits appear
to be "primarily in the reduction of urges or cravings to pick rather than
the actual behavior" "suggesting that NAC might be more effective in
people who pick automatically or with little conscious awareness." (Grant, JAMA Psych, 2016).
In men and women with trichotillomania (anxiety-related
compulsive hair-pulling) 1,200 mg to 2,400 mg of NAC taken daily for 12 weeks
significantly reduced hair-pulling symptoms compared to placebo (Grant, Arch Gen Psychiatry 2009). Another
study found daily supplementation with NAC (about 1,500 mg per day) improved
measures of obsessive-compulsive behavior in people with pathological
gambling (Grant, Biol Psychiatry 2007).
High doses of NAC were reported to reduce symptoms in four patients with progressive
myoclonus epilepsy. In the study, the patients were given vitamin E,
selenium, riboflavin, zinc and magnesium for six months, which resulted in
improvements in awareness and speech. They were then also given 4, 000 to 6,000
mg of NAC daily, plus magnesium, for over two years. During treatment with NAC,
myoclonus (involuntary jerking) was decreased (Hurd, Neurology 1996).
People with Parkinson's disease given 500 mg
of NAC orally daily in addition to 50 mg/kg (about 3,500 mg) of NAC
intravenously weekly for a period of three months showed significantly improved
symptoms as well as slightly increased dopamine transporter binding in brain
areas compared to people in a control group given standard care in a small
study in Philadelphia. There were no significant adverse events. Caveats to
this study are that it was not placebo-controlled and any contribution of the
oral NAC is likely much smaller than that NAC given intravenously. As to a
mechanism of action, the researchers noted that oxidative damage occurs in the
brains of Parkinson's patients and NAC may help by increasing levels of the
antioxidant glutathione (Monti, Clin Pharm Ther 2019).
There is interest in NAC for its anti-aging effects
due to its ability to increase glutathione levels,
which tend to decline with age. However, while some evidence from animal models
has shown that NAC increased lifespan in male mice (although not female mice),
this effect has not been reproduced in humans. Furthermore, in the animal
study, NAC supplementation reduced food intake, and dietary restriction itself
has been associated with increased lifespan (Flurkey, J Gerontol A Biol Sci Med Sci 2010).
Interestingly, NAC in combination with glycine (GlyNAC) has
also been evaluated in clinical studies for its anti-aging effect. The
combination is purportedly more beneficial than NAC alone because it provides a
source of glycine and cysteine, both of which are components
of glutathione and both of which have been shown to decrease with age and
contribute to glutathione deficiency in elderly people (Sekhar, Am J Clin Nutr 2011).
A study among eight elderly people (ages 71 to 80)
showed that supplementing with a very high dose of GlyNAC
providing about 20 grams of NAC and about 15 grams of glycine daily for 24
weeks seemed to improve several age-related defects including glutathione
deficiency, oxidative stress, inflammation, insulin resistance, and
mitochondrial and endothelial dysfunction compared to baseline, and these
improvements declined when GlyNAC supplementation was
discontinued for 12 weeks. There was also evidence that GlyNAC
supplementation modestly improved measures of attention, visual screening
ability, processing speed, verbal fluency, working memory and overall cognitive
function compared to baseline within 12 weeks of starting supplementation, and
most of these improvements declined when supplementation was discontinued (Kumar, Clin Transl Med 2021).
However, due to the small size and lack of placebo group in this study, the
evidence doesn't prove the supplement worked. Furthermore, whether or not
it increases lifespan is unknown, and it is unclear if GlyNAC
is more beneficial than NAC, as clinical studies comparing the effects of these
supplements are lacking.
Quality Concerns and
Tests Performed:
Neither
the Food and Drug Administration (FDA) nor any other federal or state agency
routinely tests supplements for quality prior to sale. In order to help consumers identify products of better quality.
ConsumerLab.com tested NAC supplements to determine whether the amounts of NAC
listed on labels matched those in the products. All products in regular
tablet/caplet form also underwent disintegration testing to check if they would
break apart properly in solution. See How Products Were Evaluated for more
information on testing.
What CL Found:
All eight of the NAC supplements that ConsumerLab.com selected
for review passed testing, as did three supplements tested through ConsumerLab.com's Quality Certification Program.
Dose:
The tested products provided 500 mg or 600 mg of NAC per capsule, 900 mg or
1,000 mg per tablet, or, among the powders, 600 mg per very small scoop or
1,200 mg per small scoop.
The total suggested daily serving sizes ranged from one to four pills per day,
yielding 500 mg to 3,000 mg of NAC. These amounts are generally in line with
what has been used in clinical studies.
"Free form":
In the Supplements Facts panels on the products, some, like Solgar, list the amount of NAC in "free
form" while others do not. With supplement ingredients that need to be
stabilized in salt forms, this distinction can be important because the free
form typically indicates just the weight of the active molecule and not the
attached stabilizer. However, NAC is always in "free form," so this
is not an important factor. That is, even those products which did not indicate
whether the NAC was "free form" were in the free form.
Cost
Since all of the products contained their listed amounts of NAC and there were
no problems with tablet disintegration, you may want to choose a product based
on price and, possibly, other special features. We calculated the cost to get
an equivalent amount of NAC (600 mg) from each product, as shown in the graph
below (as well as in brackets the last column of the Results table). The cost
to obtain 600 mg of NAC ranged over 15-fold from as just 4
cents from a powder (and 6 cents from a pill) to as much as 63 cents from an
effervescent tablet.
Top Picks:
Our Top
Picks, based on being high-quality and lowest cost for NAC, are the
following:
Powder: Nutricost NAC,
which provides 1,200 mg of NAC per small scoop (for 9 cents), was the lowest
cost source of NAC — just 4 cents per 600 mg. If you want less than 1,200 mg (a
relatively high single dose), it's easy to use less powder. The powder is meant
to be mixed into water or other beverage, but be aware
that NAC naturally has a very tart flavor.
Capsule: The capsule that provided NAC at lowest cost (10 cents per
600 mg of NAC in a vegetarian capsule) was Doctor's Best NAC Detox
Regulators. It includes 50 mcg of selenium and 50 mcg of molybdenum per
veggie cap, amounts that are at or close to the Recommended Daily Intake for these trace
minerals. Although these minerals help to convert glutathione (derived downstream
from the NAC) into its more active form, these are not necessary from a
supplement since most people get these amounts in their normal diet. (See
the CL Answer on
molybdenum for more information about this mineral). If you just want NAC from
a capsule, you actually have to pay a bit more: Our Top Pick in
this case is Life Extension N-Acetyl-L-Cysteine, providing 600 mg
NAC in a 15-cent vegetarian capsule.
Tablet: NOW NAC provides 1,000 mg of NAC per large
tablet for just 9 cents -- a very low cost for NAC, and fine if you don't need
to take a lower dose.
PharmaNAC — Pink Berry Blast effervescent
tablets were the most expensive way to get NAC (94 cents per 900 mg tablet).
Although not a Top Pick, these may be preferable for people who
have trouble swallowing pills and don't want to deal with powders, as they
rapidly dissolve in water, making a pleasant tasting drink. If you watch your
sodium intake, be aware that each tablet contains 200 mg of sodium, so the
suggested daily serving of two tablets adds 400 mg of sodium to your diet.
Test Results by Product:
Listed
below are the test results for eleven NAC supplements. Eight products were
selected by ConsumerLab.com and three others (each denoted with a CL flask) are
included for having passed the same evaluation through the Quality Certification Program.
Also shown are the amounts of NAC and serving sizes as listed on the product
labels. Products listed as "Approved" met their label claim for NAC
and ConsumerLab.com's quality criteria (see Passing Score). The full list of ingredients
is available for each product by clicking on the word "Ingredients"
in the first column, although some notable features are listed in the last
column as are price and cost comparisons.
|
RESULTS OF CONSUMERLAB.COM TESTING OF N-ACETYL CYSTEINE (NAC): |
|||||
|
Product Name, Listed
Amount of NAC per Unit, Serving Size, and Suggested Daily Serving on Label |
Claimed Amount NAC
Per Labeled Daily Serving |
--TEST RESULTS-- |
Cost For Daily
Suggested Serving On Label |
||
|
OVERALL RESULTS: |
Contained Labeled
Amount of NAC |
Disintegrated
Properly |
|||
|
|
500 mg to 1,500 mg |
APPROVED |
✔ |
NA |
$0.16-$0.48 |
|
|
600 mg to 2,400 mg |
APPROVED |
✔ |
NA |
$0.10-$0.41 |
|
|
600 mg to 1,200 mg |
APPROVED |
✔ |
NA |
$0.23-$0.47 |
|
|
600 mg to 1,800 mg |
APPROVED |
✔ |
NA |
$0.15-$0.46 |
|
|
1,000 mg to 3,000 mg |
APPROVED |
✔ |
✔ |
$0.09-$0.28 |
|
|
600 mg to 1,200 mg |
APPROVED |
✔ |
NA |
$0.06-$0.24 |
|
|
1,200 mg3 |
APPROVED |
✔ |
NA |
$0.093 |
|
|
1,800 mg (Thiolex®)
|
APPROVED |
✔ |
NA |
$1.88 |
|
|
500 mg3 |
APPROVED |
✔ |
NA |
$0.243 |
|
|
600 mg to 1,200 mg |
APPROVED |
✔ |
NA |
$0.33-$0.66 |
|
|
600 mg to 2,400 mg |
APPROVED |
✔ |
NA |
$0.33-$1.32 |
|
|
|||||
|
Unless otherwise noted, information about the products
listed above is based on the samples purchased by ConsumerLab.com (CL) for
this Product Review. Manufacturers may change ingredients and label
information at any time, so be sure to check labels carefully when evaluating
the products you use or buy. If a product's
ingredients differ from what is listed above, it may not necessarily be of
the same quality as what was tested. |
|||||
|
Copyright ConsumerLab.com, LLC, 2019. All rights reserved.
Not to be reproduced, excerpted, or cited in any fashion without the express
written permission of ConsumerLab.com LLC. |
|||||
ConsumerTips™:
There
are a number of things to look for when choosing a NAC product. First, don't be
put off if you notice a slight smell of sulfur, like that of cooked eggs.
Unless a product is coated or wrapped, you will notice this odor with most
products. This is normal and does not typically indicate spoilage or
contamination. If you purchase a powder, store it in the closed container in a
cool, dry place — away from excessive heat or moisture (refrigeration is not
necessary and could potentially expose the powder to moisture once the
container has been opened). NAC is quite stable and can be stored for at least
2 months this way without spoiling or degrading. When stored for longer periods
of times (several months to years) small amounts of NAC may degrade into di-NAC,
which is not known to be harmful and has actually been shown, in preliminary
studies, to have an anti-atherosclerotic effect, perhaps through modulation of
the immune system (Pettersson, Cardiovasc
Drug Rev 2003).
As noted earlier, the Supplement Facts panels on products may list "free
form" after listing NAC. This means that the NAC is not combined with a
salt or another stabilizer. However, as mentioned above, NAC is quite stable,
and as our tests found, all NAC supplements contain the "free form."
So even if you don't see it listed on the label as such, your supplement will
likely contain "free form" NAC.
Be aware that NAC may
not be available from some retailers based on the FDA's position that
it does not meet the definition of a dietary supplement because NAC was
approved as a new drug in 1963 and it was not marketed as a
food or supplement prior to that approval. A supplement industry trade group,
the Council for Responsible Nutrition issued
a response in December 2020 that the FDA's position on NAC in supplements was
"legally invalid." Nevertheless, Amazon confirmed in May 2021 that
it was in the process of discontinuing sale of NAC-containing supplements. Note:
The FDA's action does not appear to have been triggered by any new safety
concerns with NAC. Existing safety issues with NAC are discussed below in Concerns and
Cautions.
Dosage:
As discussed above, the dose of NAC used in clinical trials has ranged from
about 600 mg to 3,000 mg per day, typically divided into two or three servings.
See the What It Does section
for the dosage for specific uses.
NAC may be taken with or without food. However, as noted in Cautions and
Concerns section below, higher doses of NAC can cause stomach upset. If this is
the case, taking it with food may help.
Concerns and Cautions:
NAC is
generally well tolerated. However, some people may experience headache or
gastrointestinal symptoms such as nausea, abdominal pain, vomiting, constipation,
and diarrhea when taking higher doses (1,200 mg or more per
day).
NAC may also cause body odor in some people.
A study found that about 6% of people taking 1,200 mg of NAC daily (to treat a
lung ailment) reported body odor during the treatment. The researchers
attributed this to the release of hydrogen sulfide in the gastrointestinal
tract resulting from the decomposition of NAC. This may also help explain other
symptoms associated with NAC use (above) (Qi, Respir Res 2019).
NAC should not be taken with nitroglycerine except under
physician supervision, as this can cause severe headaches and an unsafe
lowering of blood pressure.
NAC may slow blood clotting and should not be taken
with blood thinners or by people with bleeding
disorders except under physician supervision. NAC has demonstrated
anticoagulant and platelet inhibiting properties in laboratory research (Nikbakht, Curr Clin Pharmacol 2017).
Also, clinical research has shown that high doses of NAC given intravenously can
decrease how long it takes for blood to clot (prothrombin time) and increase
blood loss during surgery compared to placebo (Niemi, Blood Coagul
Fibrinolysis 2006).
People with asthma should be aware that NAC has been alleged
to worsen asthma (Grant, JAMA Psych, 2016).
Women who are pregnant or nursing should not take NAC unless directed
by their physician.
NAC can interfere with results of blood tests for cholesterol (including
HDL-cholesterol) and uric acid, showing falsely low results, but
this effect is mainly of concern when large doses (several thousand milligrams)
are given within 12 hours before blood draw, such as when NAC is given
intravenously to treat acetaminophen overdose (Genzen, Clin Biochem 2016).
It is very unlikely that typical oral doses of NAC will cause interference but,
to eliminate the chance of interference, you can avoid taking NAC within a day
before blood tests.
Although the
antioxidant effects of NAC are generally protective, a study in aging mice
suggested that long-term use of NAC might increase lung cancer
development — although this has not been observed in
humans. In the mouse study, although NAC protected against the development of
emphysema, it promoted lung cancer formation during aging in 2 out of 15 mice.
An even higher proportion of mice (7 out of 14) that lacked a gene that
protects against oxidative stress developed lung cancer. According to the
researchers, "… these results support the concept that antioxidants
strongly promote tumor initiation both under abnormal conditions associated
with lung oxidative stress and during normal aging. Consequently, NAC treatment
in smokers or patients with COPD, who are at increased risk of developing lung
cancer and exhibit low JunD levels [i.e., levels of
the gene that protects against oxidative stress] in lung cells, should be
considered only with great caution" (Breau, JCI Insight
2019).
Although NAC is a sulfur-containing amino acid, being
allergic to sulfonamide antibiotics or other "sulfa drugs" (Bactrim, Eryzole, Azulfidine and others)
does not make one sensitive to NAC, due to chemical differences (ASCIA, Sulfonamide Antibiotic
Allergy).
Information on this site
is provided for informational purposes only. It is not an endorsement of any
product nor is it meant to substitute for the advice provided by physicians or
other healthcare professionals. The information contained herein should not be
used for diagnosing or treating a health problem or disease. Consumers should
inform their healthcare providers of the dietary supplements they take.
Latest Clinical Research Updates for N-Acetyl Cysteine
Why NAC Is Coming Off Retail Shelves
9/24/2021
Find out why some major
retailers are no longer selling N-acetyl cysteine (NAC) supplements. See
the ConsumerTips section of our NAC
Supplements Review.
9/14/2021
Was there a study that
showed that animals given NAC developed lung cancer? Find out what research in
animals suggested in the Concerns and Cautions section of our NAC
supplements Review.
8/17/2021
Can supplementing with
N-acetyl-cysteine (NAC) cause body odor? Find out in the Concerns and Cautions section of our NAC
Supplements Review.
7/24/2021
Can people with a sulfa
allergy (an allergy to sulfonamide drugs) use NAC, which contains sulfur? Find
out in the Concerns and Cautions section of our
N-Acetylcysteine Supplements Review.
6/08/2021
What is GlyNAC, how does it compare to NAC, and does it have
anti-aging effects? Find out in the What It Does section of our N-acetyl
cysteine (NAC) Supplements Review. Also, see our Top Picks for NAC.
Related CL Answers (11)