Last checked September 2026 against 20 sources · Editorial policy
Estradiol side effects
The most common estradiol side effects are breast tenderness or pain, headaches, nausea, bloating, spotting or irregular bleeding, leg cramps and mood changes. They usually appear in the first weeks and settle within about 3 months. Serious side effects such as blood clots, stroke and gallbladder disease are rare and more likely with tablets than patches or gels. Estradiol doesn't cause weight gain in trials.
Breast tenderness, nausea, bloating, headaches and spotting are the most common estradiol side effects. Which pass, which need a doctor, and weight.
Estradiol side effects: expectation vs reality
What people often expect
“The long list of side effects on the estradiol leaflet means most women get several of them”
What the evidence shows
The FDA label lists every effect reported with estrogen therapy, including rare ones. In practice, the NHS says it's common to have no side effects or only mild ones, and they usually improve over time. In Climara trials, headaches affected 18% of women on 0.05 mg patches compared with 10% on placebo, which shows how many symptoms happen anyway.
Estradiol side effects explained
Common estradiol side effects
According to the NHS, common side effects of estradiol, in more than 1 in 100 people, are headaches, breast pain or tenderness, unexpected vaginal bleeding or spotting, nausea, mood changes including low mood, leg cramps, a mild rash or itching, diarrhea and hair loss. The FDA label also lists bloating, abdominal cramps, dizziness, fluid retention and changes in libido. Most settle within a few weeks. If a side effect is severe or lasts longer than 3 months, the NHS advises speaking to a doctor.
Learn more →Estradiol 1 mg and 2 mg side effects
Side effects are generally dose-related. In patch trials, breast pain affected 8% of women on 0.05 mg a day and 29% on 0.1 mg, compared with 4% on placebo. Guidance counts 1 to 2 mg of oral estradiol as a medium dose and recommends starting low, because higher starting doses cause more side effects. The 2 mg tablet also contains tartrazine, a yellow dye that can cause allergic reactions in some people.
Learn more →Serious estradiol side effects
Serious side effects are rare. Estradiol tablets raise the risk of blood clots (odds ratio 1.58 in UK data), stroke and gallbladder disease; patches and gels don't raise clot risk. Without a progestogen, estradiol raises uterine cancer risk in women with a uterus. The label also lists rare effects such as raised blood pressure, jaundice, pancreatitis, vision changes and severe allergic reactions.
Learn more →Estradiol side effects and weight
The label lists both increase and decrease in weight, but trials don't show that estradiol causes weight gain. A Cochrane review found no significant difference in weight gain with estrogen, and a Danish trial found women on HRT gained slightly less fat than those without it. Early bloating and fluid retention can make you feel heavier for the first weeks.
Learn more →Side effects of estradiol and progesterone together
With combined HRT you can get estradiol side effects and progestogen side effects, such as bleeding changes, breast tenderness, tiredness or dizziness, mood changes and acne. On sequential HRT a monthly bleed is expected; on continuous combined HRT, irregular spotting is common for the first 4 to 6 months. Combined HRT also adds around 5 breast cancer cases per 1,000 women over 5 years.
Learn more →Estradiol patch vs pill side effects
Tablets are more likely to cause nausea and carry the extra clot and gallbladder risk of passing through the liver. Patches can cause skin redness or irritation where applied, affecting 3.2% or fewer women in Vivelle-Dot trials. Gels can occasionally cause a rash at the site. If one form doesn't suit you, the NHS suggests switching, for example from tablets to patches.
Learn more →Missed estradiol dose: what happens
Missing an occasional dose is unlikely to harm you. If you forget a tablet, gel or spray, the NHS says to skip it and take the next dose at the usual time. If you forget a patch change, change it as soon as you remember and then again on your usual day. Never take two doses at once. If you often forget, a phone alarm or a pharmacist's advice can help.
Ethinyl estradiol vs estradiol side effects
Ethinyl estradiol is a synthetic estrogen used in combined birth control pills, patches and rings; it isn't the same molecule as the estradiol used in HRT, which is identical to the estrogen your ovaries make. Contraceptive doses are designed to stop ovulation, and combined contraception has its own list of cautions, such as not being suitable for smokers aged 35 and over. The two aren't interchangeable.
Learn more →Estradiol side effects by the numbers
From the studies on this page
had headaches on a 0.05 mg estradiol patch vs placebo in Climara trials
18% vs 10%
had breast pain on the highest 0.1 mg patch dose, vs 4% on placebo
29%
3 months
1.58
Side effect rates are from trials of specific products. Many side effects were also common on placebo, because they overlap with menopause itself.
How to reduce estradiol side effects
Wait out mild side effects for up to 3 months
First stepHeadaches often last only a few days, leg cramps a few weeks and breast tenderness usually eases within weeks. The NHS suggests continuing for at least 3 months if you can, because side effects usually improve as your body adjusts. Keep a short diary, so you can tell your doctor what changed and when.
Take estradiol tablets with food
First stepIf estradiol tablets make you feel sick, take them with food and stick to simple meals, avoiding rich or spicy food for a while. If nausea continues beyond the first weeks, a patch or gel avoids the liver and may be better tolerated, and it also removes the extra clot risk of tablets.
Lower the dose or change the form
First stepDose-related effects such as breast tenderness and headaches often improve with a lower dose. Switching from tablets to a patch, or between patch brands, helps nausea or skin irritation. Changes are usually reviewed at 3 months. A lower dose often keeps symptoms controlled, since many women respond well to low doses.
Check your other medicines
If this is the causeSt John's wort, carbamazepine, phenobarbital and rifampin can lower estradiol levels and cause spotting or returning symptoms. Some antifungals, clarithromycin and grapefruit juice can raise levels and side effects. Tell your pharmacist everything you take. Don't start or stop other medicines without checking. Your pharmacist can check interactions each time a new prescription is added.
When estradiol side effects need a doctor
Urgent: Pain, redness or swelling in one leg
Call a doctor now. It could be a blood clot.
Urgent: Chest pain with breathlessness, trouble speaking, arm weakness or a drooping face
Call 911. These can be signs of a clot in the lungs or a stroke.
Urgent: Swelling of the lips, tongue or throat, or trouble breathing
Call 911. This could be a serious allergic reaction.
Yellow skin or eyes, a breast lump, or bleeding after months on estradiol
See a doctor promptly.
Estradiol side effects: questions women ask
What are the most common side effects of estradiol?
Breast tenderness, headaches, nausea, spotting, bloating, leg cramps and mood changes. They're usually mild and settle within about 3 months. Many women have none at all. Serious side effects such as clots are rare, and less likely with patches or gels than tablets.
Does estradiol cause weight gain?
Trials say no. A Cochrane review found no significant difference in weight gain with estrogen compared with no HRT, although the label lists weight changes and some women feel bloated at first. Weight tends to rise around menopause whether or not you take HRT.
Related →What are the side effects of estradiol 2 mg?
The same types as lower doses, but dose-related effects such as breast tenderness and headaches are more likely. The 2 mg tablet contains tartrazine, which can cause allergic reactions in sensitive people. If side effects bother you, a lower dose may control symptoms.
What happens if I miss a dose of estradiol?
Skip the missed tablet, gel or spray and take the next dose at the usual time; for a patch, change it when you remember. Occasional missed doses are unlikely to cause harm. Never double up.
Can estradiol cause hair loss?
Hair loss is listed as a possible side effect, but it's also a common menopause symptom, so estradiol may not be the cause. The label also lists unwanted hair growth. Talk to your doctor if it worries you.
Related →Can estradiol cause mood changes?
Yes, mood changes including low mood are listed as common side effects, although estradiol usually improves mood symptoms caused by menopause. If low mood persists, talk to your doctor. Progestogens are more often linked with low mood; switching type can help.
Does estradiol raise blood pressure?
An increase in blood pressure is listed among possible effects, and untreated high blood pressure needs controlling before HRT. Blood pressure is usually checked at HRT reviews. Patches, gels and sprays are recommended if you have clot risk factors such as being overweight or a past clot.
What are the side effects of estradiol and progesterone together?
A mix of both: estradiol side effects such as breast tenderness and headaches, and progestogen effects such as bleeding changes, tiredness and mood changes. Irregular spotting is common for the first months of continuous combined HRT.
Sources
- Prescribing information: Estradiol tablets USP. Teva Pharmaceuticals, 2024. DailyMed, US National Library of Medicine.
- NHS. Oestrogen tablets, patches, gel and spray: side effects.
- NHS. About hormone replacement therapy (HRT).
- Vinogradova Y, Coupland C, Hippisley-Cox J. Use of hormone replacement therapy and risk of venous thromboembolism: nested case-control studies using the QResearch and CPRD databases. BMJ. 2019;364:k4810.
- Norman RJ, Flight IH, Rees MC. Oestrogen and progestogen hormone replacement therapy for peri-menopausal and post-menopausal women: weight and body fat distribution. Cochrane Database Syst Rev. 2000;1999(2):CD001018.
- NHS. Side effects of hormone replacement therapy (HRT).
- Prescribing information: Climara (estradiol transdermal system). Bayer HealthCare, 2026. DailyMed, US National Library of Medicine.
- Women's Health Concern / British Menopause Society. Fact sheet: HRT types, doses and regimens.
- Liu B, Beral V, Balkwill A, et al. Gallbladder disease and use of transdermal versus oral hormone replacement therapy in postmenopausal women: prospective cohort study. BMJ. 2008;337:a386.
- Prescribing information: Divigel (estradiol gel 0.1%). Vertical Pharmaceuticals, 2026. DailyMed, US National Library of Medicine.
- Jensen LB, Vestergaard P, Hermann AP, et al. Hormone replacement therapy dissociates fat mass and bone mass, and tends to reduce weight gain in early postmenopausal women: a randomized controlled 5-year clinical trial of the Danish Osteoporosis Prevention Study. J Bone Miner Res. 2003;18(2):333-42.
- NHS. Utrogestan (micronised progesterone): side effects.
- NHS. Continuous combined HRT: side effects.
- NHS. Benefits and risks of hormone replacement therapy (HRT).
- Prescribing information: Vivelle-Dot (estradiol transdermal system). Sandoz, 2023. DailyMed, US National Library of Medicine.
- NHS. Oestrogen tablets, patches, gel and spray: how and when to take.
- Women's Health Concern (British Menopause Society). Contraception for women over the age of 40. Fact sheet, 2025.
- Stuenkel CA. Compounded bioidentical hormone therapy: new recommendations from the 2020 National Academies of Sciences, Engineering, and Medicine. Menopause. 2021;28(5):576-578.
- National 911 Program. 911.gov.
- NHS. Oestrogen tablets, patches, gel and spray: common questions.
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