Avoid all drugs, particularly in early pregnancy, unless your doctor prescribes them. If you buy any medicines over the counter, you must tell the pharmacist that you are pregnant. Doctors are cautious about prescribing drugs in pregnancy, particularly in the first trimester. Some drugs must be avoided altogether. Others are considered safe; these include the recommended dosage of paracetamol, and some antibiotics, such as amoxycillin and erythromycin, which may be prescribed for throat and urinary infections.
In special situations, your doctor may have to prescribe a drug that could be harmful to your baby. This will occur only if the disease for which the drug is given poses a greater risk to you or your baby's health than the drug. For example, quinine, used to treat malaria, can cause miscarriage or premature labour, but the risks from the actual disease are far greater. If you suffer with epilepsy or a thyroid condition, this will also need thorough treatment, or the consequences for you and your baby can be severe.