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Comment by rybosworld | Hacker News Reader

I was surprised when I heard they are taking phenylephrine off the market.

In my anecdotal experience, it was extremely effective at drying out my sinuses, which did reduce congestion. So I asked some family and friends and their responses were mixed. Some said it did nothing and others swore it was effective.

I'm not claiming that phenylephrine is in fact generally effective, just wondering out loud if there could be more to the story. I.e., it works for some people and not others.

Anecdotes are not science. But if enough people share an experience, sometimes there is more to the story.

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Anecdotes are the material for new hypotheses, so they are very much part of the scientific process.

This reminds me of the debate around monosodium glutamate (MSG) causing headaches. There were early scientific reports which found no real link and that it was probably psychosomatic nonsense. However more recent studies found that some people have a heightened sensitivity to glutamate, and since it is a literal neurotransmitter there is a promising pathway for the mechanism of action.

Biology is stupendously complex, it's difficult to make hard and fast rules about something being categorically effective or ineffective.

Thanks for this comment. I maintain the unpopular position that both 1) phenylephrine is mildly effective for drying out my sinuses, and 2) MSG definitely gives me headaches, unlike salt, so most likely glutamate is the culprit.

Silly fun fact, the chemical code for MSG (e621) just happens to also be the name of the largest furry "booru" site on the internet. I have no idea why this is.

What form are you talking about? The nasal spray isn’t being removed because it is effective. It’s the oral version that isn’t effective.

Also the placebo effect is real. So even if the boxes had always been packed with sugar pills, you would expect some people to report that it was effective for them.

Additionally, even if it did have some mild effect, oral pseudoephedrine is better in nearly every way.

> The oral absorption of phenylephrine is erratic. Perhaps that is why it was not used as an oral decongestant until it was the only choice. It had long been known that enzymes in the gut lining metabolized oral phenylephrine to inactive metabolites, reducing the amount of the active compound that could enter the bloodstream. The most cited study found that an oral dose of phenylephrine had an absorption rate of 38 percent of an oral dose of phenylephrine, but this study measured more than just the compound's active form. Later studies with more sensitive tests found that less than 1 percent of oral phenylephrine enters the bloodstream in an active form.

Perhaps you have a less active form of the enzyme that degrades it.

My anecdote is that for me I've known phenylephrine worthless for decades and seek out pseudoephedrine when I need actual relief. Now we have two data points.

> Anecdotes are not science. But if enough people share an experience, sometimes there is more to the story.

Solely relying on anecdotes as evidence is not science, but they’re absolutely a critical part of it!

Science is expensive and moves slow. Sometimes anecdotes are all you have.

Just because the science doesn't exist doesn't mean anecdotes are completely invalid.

That's what I was trying to say. Anecdotes are the seeds of hypotheses, and enough anecdotes with well-understood conditions make a study population.

> Science is expensive and moves slow.

I don't know if I agree that science is slow. Certainly scientific consensus is slow though. The churn of ideas at the forefronts of fields is rapid. In my field (machine learning/statistics) I'd say too rapid/short term incentive focused.

I really take umbrage at the idea that science is some purely objective, ideal process. It's messy, and scientists are opinionated and stubborn. Some of the most obstinate people I've met are tenured professors... They kind of have to be. It takes time for good ideas to weather the initial criticisms, persist through replication and testing, and to take hold.

Science is slow for sure. You need to gather samples and run tests. Often testing for causality is impossible, because you literally need to "cause" the issue in your sample group and that raises ethical issues if the thing you're "causing" is harmful.

It's not even the human parts that are flawed with science either.

Science is fundamentally flawed by nature because in science and therefore reality as you know it you cannot prove anything to be true. You can only falsify things in science. Proof is the domain of mathematics.

I had the same experience with phenylephrine. It dried out my sinuses, which helped me slightly with decongestion but moreso with post-nasal drip.

The effect was not dramatic, and as I understand it, people with allergies need that dramatic effect to be able to breath well.

It seems to me phenylephrine was effective for something different than what the FDA had in mind, but due to their folly, now both phenylephrine and pseudoephedrine are unavailable to the average person.

I've been looking for this comment in all these stories regarding the ineffectiveness of phenylephrine!

I have a similar story. Congestion is not a symptom I typically get. Covid, however, decided to shake things up and introduce me to a new set of symptoms... One of those was congestion such that my head felt like a balloon. Without experience treating this symptom, I went out and ended up with Sudafed PE, oral phenylephrine. It worked _immediately_, it was like a balloon deflating. It worked so well that these headlines regarding phenylephrine's ineffectiveness still cause bemusement...

anddd that's my story.

Are you referring to tablets or nasal spray?

I think the fact that different drugs work differently on different people is criminally underrated.

Anecdotes are not science. But if enough people share an experience, sometimes there is more to the story.

Read that again in context to the two people who found the science of why it does not work..

You are defeating your argument...

There is a problem with the studies these pharmacists are referencing. They are measuring nasal resistance, however, the measurement is not sufficient to capture the combination of things that make up nasal resistance. It's a combination of how much mucus is being secreted vs the degree of sinus inflammation.

New theory: Allergy sufferers are likely primarily experiencing sinus inflammation. Pseudoephedrine is the better solution for that. For those of us who are dealing with secretion - phenylephrine is effective.

https://www.jacionline.org/article/S0091-6749(06)00633-6/ful...

What’s a case study but a fancy anecdote? It’s not very sciencey to form an opinion after a study and shut down conflicting evidence.

I don't think you've made the point you intended to.

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