Different people respond differently to drugs. Some drugs produce an adverse reaction in some people, and exposing them to varying degrees of risk. People at special risk include infants and children, pregnant or breast-feeding women, elderly and people with long-term medical conditions, especially those who have impaired liver or kidney. Our focus being JUSTEVES, we shall discuss only pregnant and breast-feeding women.

When doctors prescribe drugs for special risk group they take extra care to select appropriate medication, adjust dosages and closely monitor the effects of treatment. If you think you may be at special risk, be sure to tell your doctor in case he or she is not fully aware of your particular circumstances. Similarly, if you are buying over – the - counter drugs you should ask your doctor or pharmacist if you think you may be at risk from any possible adverse effects.

PREGNANCY

Great care is needed during pregnancy to protect the foetus so that it develops into a healthy baby. Drugs taken by the mother can cross the placenta and enter the foetus’s blood stream. With certain drugs, and at particular stages of pregnancy there is a risk of developing abnormalities, retarded growth or post-delivery problems affecting the baby. In addition, some drugs may affect the health of the mother during pregnancy.

Several drugs are known to have adverse effects during pregnancy, others are known to be safe, but in large number of cases there is no firm evidence to decide on risk or safety. Therefore, the most important rule if you are pregnant or trying to conceive is to consult your doctor before taking any prescribed or over-the – counter medication. Your doctor will balance the potential benefits of drug treatment against any possible risk to decide whether or not a drug should be taken. This is particularly important if you need to take regular medication for a chronic condition such as epilepsy, high blood pressure or diabetes.

DRUGS AND THE STAGES OF PREGNANCY

Pregnancy is divided into three, 3-month stages called trimesters. Depending on the trimester in which they are taken, drugs can have different effects on the mother or the foetus or both. Some drugs may be considered safe during one trimester, but not another. Doctors, therefore, often need to change regular medications given during the course of pregnancy.

First Trimester

During the first 3 months of pregnancy, the most critical period, drugs may effect the development of foetal organs, leading to congenital defects. Very severe defects may result in miscarriage.

Second Trimester

From fourth until sixth month some drugs may retard the growth of the foetus. This may also result in a low birth weight.

Third Trimester

During the last 3 months of pregnancy, major risk includes breathing difficulties in the newborn baby. Some drugs may also affect labor, causing it to be premature, delayed or prolonged.

HOW DRUGS CROSS THE PLACENTA

The placenta acts as a filter between the mother’s blood stream and that of the baby. It allows small molecules of nutrients to pass into the baby’s blood, while preventing larger particles such as blood cells from doing so. Drug molecules are comparatively small and pass through this placenta barrier.

How Drugs Pass Into Breast Milk

The milk producing glands in the breasts are surrounded by a network of fine blood vessels. Small molecules of drugs pass from the blood into the milk. Drugs that dissolve easily in fat may pass across in greater concentrations than other drugs. This means that a breast fed baby may receive small doses of whatever drugs the mother is taking. In many cases this not a problem because the amount of drug that passes into the milk is too small to have any significant effect on the baby. However, some drugs can produce unwanted effects on the baby. Antibiotics may sensitize the infant and consequently prevent their use later in life. Sedative drugs may make the baby drowsy and cause feeding problems. Moreover, some drugs may reduce the amount of milk produced by the mother.

Doctors usually advise breast-feeding women to take only essential drugs. When a mother needs to take regular medication while breast-feeding, the baby may also need to be closely monitored for possible adverse effects.