Nearly everyone can take NAC.

Healthy people with low levels of toxicity and adequate levels of glutathione probably don't need NAC, but it's nearly impossible to avoid toxins these days. There is at least one source out there that says NAC should be used with caution in those with a history of peptic ulcer disease. This most likely refers to tablets and capsules that remain undissolved in the stomach for varying times, which is why effervescent is not likely to cause irritation. If you have a peptic ulcer, consult your doctor if you're considering NAC. Supplemental NAC should be avoided by nursing mothers and should only be used by pregnant women if prescribed by a physician. People who form rare cystine renal stones should consult a physician about NAC and drink 6-8 glasses of water daily if you choose NAC. You may want to lower your dosage if you are a petite person, or if you have any gastrointestinal distress, nausea, or vomiting, again not as likely with Effervescent NAC. The vast majority of reports we've read assert the safety and lack of side effects, but it's slightly possible that someone out there may be sensitive. We want you to be well informed.

The largest list of drug interactions we found was published by the Atlanta Journal Constitution. Many drugs are enhanced by NAC. Below is an excerpt from that page.

Possible Interactions

If you are currently being treated with any of the following medications, you should not use cysteine supplements without first talking to your healthcare provider.

Blood Pressure Medications, Angiotensin-converting Enzyme (ACE) Inhibitors
NAC may enhance the blood pressure-lowering effects of ACE inhibitors, medications commonly used to treat high blood pressure. Examples of ACE inhibitors include benazepril, captopril, enalapril, fosinopril, lisinopril, moexipril, quenipril, ramepril, and trandolapril.

Immunosuppressive Medications
Treatment with NAC may enhance the effectiveness of immunosuppressive medications such as azathioprine, cyclophosphamide, prednisolone, or prednisone. More research in this area is needed.

Cisplatin and Doxorubicin
Laboratory and animal studies have suggested that NAC may reduce the toxic effects associated with both cisplatin and doxorubicin, medications used to treat a variety of cancers. However, scientific studies are needed to see if these effects apply to people.

Nitroglycerin and Isosorbide
Although NAC may enhance the effectiveness of nitroglycerin and isosorbide (two medications commonly used to treat chest pain), this combination may also increase the risk of side effects such as severe headaches and may lead to abnormally low blood pressure.

Oxiconazole
Topical applications of NAC may increase the effectiveness of oxiconazole, an antifungal medication used for athlete's foot.

From PDRHealth:
Interactions
Nitrates: Use of supplemental NAC along with nitrates may cause headaches.

Carbamazepine: Use of supplemental NAC along with carbamazepine may cause reduced serum levels of carbamazepine.

No interactions with nutritional supplements, food or herbs are known.
There has been some rare mention of possible headache, gastrointestinal distress, nausea or vomiting for some.

Also, check this link for more info: Health Notes

Make sure you do your homework and look through our pages and links to reports that we've found. Educate yourself: your health is your responsibility.

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