2 Blood Pressure Meds Recalled For Possibly Containing A Cancer-Causing Substance

[NNadir]

11. Nitrosamines are well known for all of the "sartans," and relates to the neutralizing of azides...

...used for cyclization of the nitrile to give the tetrazole ring with sodium nitrite.

This avoids the use of expensive tributyltin azide.

The original case was for valsartan, made by Huahai in China.

It turns out there was a highly responsible reason for doing this, the decision to recycle a solvent, DMF, to avoid costs and to reduce environmental impact.

Subsequent to this discovery, the FDA and foreign regulatory agencies began to regulate nitrosamines in a number of other compounds, including other sartans, and notably, metformin. The OTC compound ranitidine was pulled from the market.

The largest, by far, source of carcinogenic nitrosamines, on a scale vastly exceeding anything found in pharmaceuticals is cigarette smoke. The second largest source of it, again, dwarfing pharmaceuticals, is cooked meat, especially cooked preserved meat; notably bacon and other pork products, many of which are preserved using nitrites.

I take valsartan, and for a while couldn't get it, since most of the world supply of the active ingredient was manufactured Huahai, and that which wasn't, was sold out. As a result, my doctor switched me to losartan, later found to also contain nitrosamines.

The sartans control my blood pressure very well. (This is a good thing, since, before discovering the "ignore" button at Democratic Underground, people talking out their asses about scientific subjects about which they clearly knew nothing used to raise my blood pressure considerably.) My doctor asked if I'd like to switch to some of the dipeptide agents, which I tried well before I was his patient. These induce uncontrollable coughing for me. This means I have a mutant ACE2 receptor, which is the receptor to which SAR-Cov-2 binds. This lead me to make lots of rather off color jokes before the vaccine about being a mutant who was superpowered in resistance to Covid. (This of course, was sarcastic nonsense with no scientific basis, and as soon as possible, I ran to get vaccinated.)

I told my doctor, I'd rather risk cancer from nitrosamines than a stroke, even though I have identified that I possess a gene for Barrett's esophagus. Both my father and my uncle's initial cancers were esophageal, and both were heavy smokers, and both loved bacon and pork dishes. (I don't eat cows, pigs, chickens etc...but not because of any concern about nitrosamines, but because I could never kill a cow, pig or chicken, etc...and thus am unwilling to pay other people to do what I would never do myself.)

The mechanism by which nitrosamines cause cancer is interesting. The nitrosamines decompose to give diazo compounds which specifically alkylate guanine residues in DNA. The regulatory agencies around the world cannot agree on which nitrosamines are important, although there is some commonality.

I'll bet you that many of the people here bashing Lupin know very little about this subject, very little about risk, and for that matter are unconcerned when eating well cooked bacon, although they should be.

From a pure risk perspective, it is, in my opinion, far more dangerous to fail to control one's blood pressure than to risk cancer from nitrosamines. I chose to continue using valsartan, since I am a scientist and I understand that all drugs contain risk, and that intelligent choices in one's health, not only in pharmaceuticals but in other areas (such as energy) one cannot be risk free, only risk minimized.

Nitrosamines are found, for the record, in most water supplies, albeit in concentrations lower than pharmaceuticals. The culprit is urea from urine in outfall pipes and chlorine in purifying those supplies.

Here is one of many hundreds of paper published this year on the topic: Aqueous N-nitrosamines: Precursors, occurrence, oxidation processes, and role of inorganic ions (Tahereh Jasemizad, Peizhe Sun & Lokesh P. Padhye Critical Reviews in Environmental Science and Technology (2021))

For those who like pictures, here's a picture from the text:



NDMA (nitrosodimethylamine) is the most famous nitrosamine. There are many others.

Have a nice day.