"Hard on the liver or kidneys" means that the medication is making this organ work harder, damaging it or so potent that the medication is harder to rid from the body.
Thinking about the liver:
It helps clean your blood by getting rid of harmful chemicals that
your body makes
Liver Injury Caused by Drugs
The pathophysiology of DILI varies depending on the drug (or other
hepatotoxin) and, in many cases, is not entirely understood.
Drug-induced injury mechanisms include covalent binding of the drug to
cellular proteins resulting in immune injury, inhibition of cell
metabolic pathways, blockage of cellular transport pumps, induction of
apoptosis, and interference with mitochondrial function.
In general, the following are thought to increase risk of DILI:
Age ≥ 18 yr
Concomitant alcohol consumption
Genetic polymorphisms (increasingly recognized)
Patterns of liver injury DILI can be predictable (when injury usually
occurs shortly after exposure and is dose-related) or unpredictable
(when injury develops after a period of latency and has no relation to
dose). Predictable DILI (commonly, acetaminophen-induced) is a common
cause of acute jaundice and acute liver failure in the US.
Unpredictable DILI is a rare cause of severe liver disease.
Subclinical DILI may be underreported.
DILI stand a for drug induced liver injury. And like the phrase "Hard on the liver" the drug doesn't have to lead to immediate damage, but damage over time like from alcohol. There are tests for this to.
Thinking about the kidneys:
Pain meds reduce blood flow to kidneys.
Some meds are harder to excrete so lower doses or no doses are neccesary. This is another meaning of "Hard on the kidneys".
the use of a contrast dye is necessary to enhance these tests, but
sometimes these dyes can either lead to kidney problems, or cause
problems in patients with kidney disease.
Just some background on how meds can be "hard" on the body. The term hard is suppose to indicate how it negatively affects the body.
Taking vitamins doesn't have to be hard on the body.
Taking a vitamin or supplement as directed on the package label is
considered to be safe, but not following directions can lead to
Vitamins are a needed medicine in everybody. Taking more than is needed is unhealthy and can damage you. However, the recomended amount is healthy for you. Other medicines are harsh chemicals meant to fight powerful disorders so there are side effect. B complex vitamins are usually ok in proper doses, yellow urine is a side effect seen in some peopke. The harm it may do does not outweigh the good.
Riboflavin is required for the proper development and function of the
skin, lining of the digestive tract, blood cells, and many other parts
of the body.
The Recommended Dietary Allowance (RDA) is the average daily dietary
intake level that is sufficient to meet the nutrient requirement of
nearly all (97 to 98 percent) healthy individuals in a particular
gender and life stage group (life stage considers age and, when
applicable, pregnancy or lactation).
RDA is created so that we know what is best to take for our bodieses not the best solution is to ask the doctor the reasoning behind this and if i without damaging them or causing them deficiency. Sometimes the amount recommended by a company or doctor may not match the RDA, if it is done by the company consulting your doctor on whether the amount is safe. This is because sometimes a doctor may prescribe a higher amount if you are having a deficiency or on a medicine that lowers this level or etc. Taking the amount can hurt you by toxicity, overtime or deficiency so it is best to be safe. You should make sure when measuring amounts you know what is best for you a good rule of thumb is to stay between recommended minimums and maximums, also consulting the doctor or a pharmacist helps to find the amount for you. As the doctor can run test to see your levels in the blood and see what to take for different age, gender or weight groups. This may seem like a wasted visit, but nutrition is important and it can harm you if done wrong.