Prolonged use of estrogens may cause some adverse effects on the person such as headache, breast discomfort, dizziness and vomiting, gastrointestinal disturbances, gas, hair growth, changes in sexual desire, etc..
In the most serious cases, estrogen drugs can cause loss of appetite, weakness, hives, abdominal swelling, joint pain, etc..
For this reason, an estrogen treatment should always be applied under a doctor's prescription.
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