Read any of the popular press (as opposed to the scientific medical press such as the Lancet, for example) and you will read about vaccines being developed to save us all from AIDS, cancer, next year’s giraffe flu and halitosis.
Unfortunately, the next generation vaccines and drugs are still in the testing phases, because they need rigorous testing. Remember that in 1976 a vaccine was rushed through by order of an American president, and I believe more people died from the vaccine than died from the flu from which it was supposed to protect the public. It also left a large number of people with a nasty condition called the Guillain-Barré syndrome, and about 30 percent of those with Guillain-Barré still have a residual weakness.
Have you ever wondered just how a new drug finds its way on to the pharmacist’s shelves? Just how do the pharmaceutical companies manage to develop newer vaccines and drugs such as ACE inhibitor antihypertensives when there were already plenty of alternatives? Or the apparently stiff competition in the drugs for males with Erectile Dysfunction. (I am sure you have all been receiving emails every day offering you longer and stronger lead for your particular pencil!)
However, when any new medication is formulated, there begins a very long process before the new “wonder drug” is licensed for use by the public. Part of that process is testing the compound on live beings. Note I did not say “human” beings. Those live beings are usually convenient test animals, of which Mr. Rat the rodent is a prime example.
We always need to know how poisonous is the new drug. Mr. Rat is then fed the new compound in ever increasing quantities until the dose high enough to kill 50 percent of the rat population is reached. The scientists call this the LD50 (Lethal Dose for 50 percent) for the new compound – but remember this is for rats. If it takes 10 mg of compound A to kill 50 percent of the rats, but only 1 mg of compound B, then B is 10 times stronger than A.
Pregnant Mrs. Rats are also fed the new drug and the offspring are thoroughly examined to see if there are any abnormalities, greater than the ‘normal’ amount of expected abnormalities. Yes, no animal, including us, is without a usual percentage of birth abnormalities. Laboratory rats in particular are well known for being able to develop all sorts of abnormalities if you even just look at them sideways!
Only after this exhaustive testing is the drug then used in limited test runs on a very limited human exposure group. And, by and large, that does not include testing on productive age females.
All this takes an enormous length of time, so next time you read of the new wonder drug “breakthrough” do not expect that this will appear in the pharmacy next week. Unfortunately too, many of these new drugs will end up never being released as further research often turns up problems that only made themselves apparent after long term usage.
However, even the ones that do get released have to be approached with caution. Just because rat testing appeared to show that the drug was “safe”, does not mean that humans will also react the same way. As the caption this week says, Man is not a large Rat! This is one reason why women in particular must be very careful with the drugs they take during pregnancy, particularly in the first three months, that time when the growing fetal structures are susceptible to toxic chemical damage. In fact, any woman who has to take regular medication should ask her obstetrician about the relative risks. However, this does not mean stop taking the tablets as soon as you miss a period. Letting the maternal problems run unchecked can be an even greater risk to the baby than the risk from the medication taken by Mum.
Antenatal care is a very specialized branch of medicine and I do recommend you should ask your obstetrician for advice. You may not be a rat – but you don’t want to be a guinea pig either!
