Good news for mums-to-be

The good news is that all the common allergy medicines are known to be remarkably safe in pregnancy.

Not only should you be able to enjoy your pregnancy without suffering unduly from asthma and allergies, but good asthma control is especially important when you are pregnant.

With newer medicines there is often no formal information about safety in pregnancy. Nowadays, when new drugs are tested, women who are or might become pregnant are not allowed to take part in the safety tests. This means that we do not have the same information on safety in pregnancy which we have for people who are not pregnant. The reason for this is obvious. No manufacturer wants to take the least risk with unborn babies.

But older medicines have been used for a long time before the thalidomide catastrophe taught us that unborn babies have a special risk. They were all used in pregnancy, and all the common ones amongst them are known to be safe in pregnancy.

In the case of newer medicines you should avoid them in pregnancy if possible, just in case. But there are usually older alternatives. In time it becomes obvious for each newer medicine that it must be safe, because many women do not know at first that they are pregnant, and so take common medicines like the rest of us. Willy-nilly, these women act as 'guinea pigs' for the rest of us. This may upset you; if you are a woman and are concerned about this, the rule is: don't take medicines which have not been used by millions of people and for at least three years if there is any possibility, however remote, that you might be pregnant. Unfortunately, human life being what it is, surprisingly many women do not admit to themselves that they might be or become pregnant when they have sexual intercourse.

In practice, there is a good choice of medicines which is either known to be highly safe in pregnancy or which must at least be safe enough for all ordinary purposes.

When a baby is conceived, you don't know whether it is going to be a boy or a girl. You don't know whether it will be more clever or less so. We take the chance happily. Some pregnancies, at the best of times, end in loss of the baby, and of course a few babies are born with illnesses and defects, even to mums who have not been anywhere near medicines. That is part of life. Again, we normally accept these chances when we decide we want a baby. The point is that the overwhelming majority of problems have nothing at all to do with medical treatments.

But what about my medicine?

• Preventers
  • Steroid inhalers

    Becotide (beclomethasone dipropionate, now a common drug under all sorts of other names too) was made prescribable in 1972. In the 26 years since then, it has been used by vast numbers of pregnant women with asthma, without any known harmful effect in their babies. In fact one medical expert after another, reviewing the evidence, has concluded that the use of it and other inhaled steroids protects unborn babies from the risks of getting too little oxygen when its expectant mum has asthma. Experiments with huge doses in animals have shown harmful effects on the offspring, but these doses are enormously higher than anything a human being could take. At doses which are not so enormous, but still higher than anything a human being could take, no harm occurred.

    Pulmicort (budesonide) has likewise been used for very many years and on a huge scale, including a huge amount of use by women who were pregnant. No evidence of harmful effects, and plenty of evidence of protection of the baby from lack of oxygen.

  • Cromoglycate (Intal, Lomudal, Cromolyn etc.) and Nedocromil (Tilade, Tilarin, etc.)

    These asthma preventers are not steroids, and their safety record is wonderful. No harmful effects on unborn babies have ever been recorded despite widespread use from 1968, when cromoglycate (Intal) was introduced in Britain, until the 1980s, since when its use has declined because of the greater effectiveness of inhaled steroids. They are still excellent medicines for people in whom they prove sufficient.

  • Theophylline (many trade names)

    Theophylline was never as widely used in Britain as in the USA, and its use is declining as regular treatments relative to inhaled steroids. Unlike inhaled drugs, theophylline is taken by mouth, usually as tablets, and unlike the inhaled steroids it is not broken down too quickly in the liver to prevent it from working on other parts of the body in addition to the lungs. Significant amounts would be expected to reach the unborn baby. Despite widespread use however, no harmful effects on unborn children have been described. Our personal preference is not to use tablets such as theophylline in pregnancy, even though we don't know of any harm.

• Relievers (bronchodilators)
  • Salbutamol (Ventolin, many other brand names)

    Salbutamol has been in widespread use since the 1960s. When given in large doses by infusion or injection near the time when the baby is to be born, it can delay birth, and in fact it has been used for this purpose. In doses which are more usually inhaled for asthma it is harmless even then. Of course if you need very large doses for an asthma emergency near the time of birth, these will have the same effect in slowing or preventing birth. All the more reason to get particularly good control of your asthma when you are pregnant. The aim should be not to have an asthma emergency at such an important time.

    Terbutaline (Bricanyl) is very similar to salbutamol. All the conclusions for salbutamol should apply.

• Long-acting relievers
  These work in the same way as the ordinary relievers such as salbutamol and terbutaline, with the difference that they stick to the cells in the body on which they act, and so work for much longer. The side-effects are the same, namely tremor, increased pulse rate, and palpitations (being able to feel your heart beating). They have been introduced much more recently, but no hazards in pregnancy are known.
  • Salmeterol xinafoate (Serevent)

    No further comment.

  • Eformoterol (Foradil)

    No further comment.

• Steroid tablets or injections
  You should only need these for emergencies or bad worsening of your asthma, or if your asthma is so bad all the time that you are one of the few people who do need them regularly. If so, you need them, and your baby would be much worse off if you did not take them.

  Many other diseases are treated with steroid tablets or injections. In particular one disease, systemic lupus erythematosus, is an illness which affects women of childbearing age. Lots of them have been treated with steroid tablets during pregnancy. Such steroids do affect the unborn child, but the effect is remarkably mild. If you have to take steroid tablets, discuss this with your specialist: you should be under the care of an asthma specialist if you are on regular steroid tablets. Everyone will want to get you off the steroid tablets if that is possible, or at least to minimise the dose. If you cannot come off them though, make sure you have had the risks and benefits explained to you, make the best decision, and then don't worry more than the facts justify. And the facts are remarkably reassuring.

Asthma when you are expecting a baby: the reasons why good treatment is specially important

There are no known harmful effects from inhaled steroids (or any preventer inhaler) and bronchodilators (or any reliever inhaler used within reason). And this is despite many serious attempts to check whether there might be some harm, and widespread experience of these drugs in pregnancy over decades.

Many experts over the years have looked at all the evidence. They have all come to the same conclusion; keeping asthma well treated in pregnancy pays dividends in protecting the unborn baby, and no side effect comes close to cancelling the real benefits from the treatment.

That's all very well, but doctors don't know everything. I'd like to keep medicines to a minimum anyway, specially whilst I am carrying my unborn baby.

First of all, don't smoke. Smoking is bad for your baby in several ways. Smoking causes asthma-like changes in your baby's lungs, for example. Smoking is also bad for your asthma. If you don't smoke you will probably need less medicine.

Smoking by others who are with you is also bad, though not as bad as smoking yourself.

Do what you can to avoid allergic causes of asthma such as pets and house dust mites. You can read about some of these in other parts of these web pages. By keeping away from the causes of asthma you will also reduce the amount of medicine you are likely to need.

Get good advice about your asthma, and take your regular treatment regularly. By doing this you will be less likely to have worsening of your asthma or even an emergency. In other words, regular steady preventer treatment means that you are much less likely to need big doses of drugs because of worsening asthma.

Will my asthma get worse, or better, whilst I am pregnant?

A few women get asthma for the first time whilst they are expecting. Or you may have had asthma as a child and get it again whilst you are expecting. These things can happen at any time of life, but because pregnancy sometimes has a bad effect on asthma, they may happen particularly at this time. There's no need to panic. Here's what you should do. Go to your doctor and make sure you get not just the same attention as anyone else with new asthma, but a bit more. After all, there are two of you to consider (at least!). If your asthma has just started or re-started, this means your lungs are basically very close to normal, so treatment should be very effective.

Just very rarely asthma can be vicious just in pregnancy, and the expectant mum has to be admitted to hospital to control the asthma. Although this is bad, such asthma gets much better again after pregnancy, so there is at least some good news. If you are in this situation, try to get treated by an asthma specialist, and not only the obstetrician or a general physician.

In short, the rules for dealing with asthma in pregnancy are basically the same as at other times, and the difference is mainly that you should just get more attention and care than most people get at other times.

What about treatments for other allergies such as hay fever if I am expecting?

The steroids which we use for sprays for the nose in hay fever and similar allergies are the same ones which are so safe in asthma . They should be just as safe when you use them for your nose, at least if you stick to normal doses.

The commonest antihistamines seem to be safe as well. The old sedative ones in common use were investigated in great detail, and turned out to be safe. The newer antihistamines, which don't make you sleepy, could not be investigated this way because women and doctors now avoid using drugs during pregnancy. But in practice it happens often that women take medicines without knowing that they are pregnant. If a baby is born with a malformation, people always enquire whether it could have been caused by a drug which the mother took whilst she was pregnant. This surely means that the commoner antihistamines of the newer generation which have been around for the longest time, such as fexofenadine and cetirizine, must be safe by all reasonable criteria. Some people might be puzzled at my inclusion of fexofenadine, a rather new drug. But it is not nearly as new as it seems. Its formerly widely used predecessor, terfenadine, was turned into fexofenadine in the body. So expectant mothers have probably been exposed to fexofenadine more than to any other antihistamine, and we know more about its safety.