What does it mean for medication to be "hard on the stomach"?

In this thread, INSANE1 mentioned in passing that you should take a certain supplement with food, because it is quite hard on the stomach.

What exactly does it mean for a medication or herbal supplement or whatever to be hard on the stomach and/or for it to say “take with food”? What happens if you don’t take it with food? Will you have stomach pain? Get diarrhea? Get an ulcer? Start vomiting blood?

Or does it entirely depend on the particular medication?

I know that a lot of times I’ve taken medicine that said “take with food” on an empty stomach. I don’t recall having any trouble (except with one antibiotic I can’t recall the name of, but it gave me a horrible stomachache even with food) but could it be that I’m slowly giving myself an ulcer? I rarely take aspirin, but I do take ibuprofen and naproxen sodium and the like.

How about (e) any or all of the above.

Some meds will just nauseate you, some will burn and hurt, some will cause ulcers, some will make aliens grow out of…no, wait, that’s Sigourney Weaver movies…

Seriously, it depends on the medication, the supplement, whatever. As a rule of thumb, unless the directions specify taking it on an empty stomach, you’d be better off with something going down before or with it. Some of that stuff can seriously jack with your body, man.

My experience? I have had a semi-gastrectomy for cancer, and yet I can take Vioxx without food, no problem. Celebrex, which is very similar to Vioxx, caused ‘distress’ (pain and noise/gas) with the first dose, and bleeding with the second. THAT makes no sense, but that’s what happens.

Oh, and drink at least 8 ounces of water with your meds, so that they go down to your stomach on the waves…otherwise they’ll hang out and erode your esophagus!! (My pharmacist told me so, and I believe him. Sorta.)

Quite a few medications suggest taking them with food. There can be several reasons for this. The most common reason is probably that the medication is absorbed too rapidly on an empty stomach; taking them with food leads to slower absorption and a longer duration. Some medications are more ‘bioavailable’ if taken with food; you absorb more of the medication, rather than having it pass through you unabsorbed.

Some medications can cause problems if they’re taken on an empty stomach. In some cases, the acidity or basicity of the drug might be a factor. With some anti-inflammatory/pain-reducing drugs, a more direct mechanism is responsible.

Non-steroidal anti-inflammatory drugs (NSAIDs) work by blocking the synthesis of prostaglandins, which are responsible for various things including inflammation – but some prostaglandins, such as one called PGE1, are responsible for protecting your stomach and duodenum from the concentrated acid in your stomach.

Fortunately, the ‘good’ prostaglandins use a different enzyme (COX-1) than the ‘bad’ ones (which are made by COX-2). Early anti-inflammatory drugs – aspirin is notorious for it – block both COX-1 and COX-2, and can cause severe stomach problems. Some newer NSAIDs block only COX-2, and leave the stomach-protecting prostaglandins intact. Vioxx is one of these.

However, COX-1 is also implicated in some types of inflammation, particularly arthritis. So the most effective NSAIDs for arthritis block both COX-1 and COX-2 to different extents. Celebrex would be such a drug.

Unfortunately, thatDDperson, I can’t find any numbers to indicate how specific Vioxx and Celebrex are for COX-1 and COX-2. But I’d think your experience with the two drugs suggests that Vioxx – which doesn’t irritate your stomach even if you take it without food – only inhibits COX-2. And Celebrex, an anti-arthritis drug, inhibits COX-2 but also inhibits COX-1 to some extent – so it interferes with the stomach-protecting prostaglandins, and causes problems if you take it on an empty stomach.

If you don’t have arthritis, you might consider asking your doctor to discontinue the Celebrex if it’s a common problem, especially if you occasionally experience problems even if you take it with food.

NSAIDs can cause ulcers if taken long enough. There’s an article about that here.