How long does an estradiol patch take to work? (+1 steps)

In this article, we will discuss the timeframe for the estradiol patch to exert its effect. Estradiol patch is used for estrogen replacement therapy, often prescribed to women undergoing menopause.

How long does an estradiol patch take to work?

Estradiol patch may take 1-2 weeks to start showing its effect (1). You may see minor improvement within a few days, but for some women, it may take several weeks and months for steady improvement in the symptoms associated with menopause. 

Physical symptoms may improve first, for example, you may observe that hot flushes and night sweats are significantly better after 4-6 weeks. However, substantial improvement in psychological factors like mood swings, anxiety, and depression may take a few months.

Estradiol patch is prescribed to females having menopause due to the changing amount of hormones in their body. You will be asked to wear an estradiol patch if you experience profound night sweating, hot flushes, irritability, and extreme mood swings due to menopause.

You may also wear an estradiol patch if your uterus has been removed surgically (hysterectomy). The estradiol patch is for external use only. Do not apply more than one patch. Always apply the patch on dry, clean skin. Ask your pharmacist for the proper use and application of the estradiol patch.

How long does estradiol stay in the body?

The estradiol patch contains estrogen hormone. It is applied on the skin after 3-4 days to provide sustained delivery of estrogen in the body. The half-life of estrogen in the body is short (about 1 hour). Due to its transdermal route, the first-pass metabolism is avoided. 

After application, the maximum plasma estrogen concentration is achieved within 2-8 hours. The bioavailability of the estradiol patch is better than the tablet and transdermal gel. However, the fluctuation in the estrogen level is also comparatively higher (2).

What does research suggest?

A randomized double-blind study conducted on 603 women showed that an estradiol patch (0.05 or 0.1 mg/day, 7-day sustained transdermal patch) exerted its effect within 1-2 weeks of starting the therapy. The efficacy of the estradiol patch was fully sustained over the 7-day patch wear.

A slight reduction in effect was seen during each cycle’s treatment-free week. The therapy was well tolerated, however, 8.9% of the women dropped out of the study due to adverse effects. Amongst these, 6.8% of the females experienced skin irritation (1).

Both the estradiol patches reduced the occurrence of hot flushes. For the 0.1 mg/day release patch, a 74.6% reduction was observed, whereas the 0.05 mg/day patch reduced the hot flushes by 64.5%. No drug accumulation occurred after 7 days, verifying the safety of the patch (1).

In a randomized, crossover study, it was established that transdermal estradiol patch has better bioavailability than transdermal gel and tablets. The estradiol patch resulted in very consistent estrogen levels over the middle part of the wearing duration (3). 

Factors affecting the time taken by an estradiol patch to work

Several factors may affect the time taken by an estradiol patch to work, including:

Dementia

Women with dementia may forget to wear the estrogen patch. Therefore, her caregiver must keep track of the dosage regimen prescribed by the doctor. An alarm, reminder, or markings on the calendar may help keep track.

Vaginal bleeding

If you experience heavier vaginal bleeding or spotting that occurs for more than one week, immediately consult your doctor. You may need to discontinue wearing the patch or remove it for a short time as per the directions of a doctor.

Cholesterol level

Estrogen is known to increase the amount of cholesterol relative to bile salt and lecithin in bile, especially when given orally. This increases the saturation of bile with cholesterol, leading to the formation of crystals. However, such side effects are minimal with estradiol patch.

What are the side effects of an estradiol patch?

Some of the side effects caused by estradiol patch may include:

• Vaginal spotting or bleeding,
• Breast tenderness,
• Abdominal bloating,
• Endometrial hyperplasia,
• Leg cramps, and
• Nausea. 

Adverse effects of suddenly discontinuing an estradiol patch

If the use of an estradiol patch is discontinued suddenly, it may cause estradiol withdrawal symptoms. Perimenopausal depression (PMD) may return in women who were previously wearing estradiol patch during menopause.

Other adverse effects may include hot flushes, mood swings, irritability, anxiety, depression, and night sweats. Some women also complain of headaches, bloating, abdominal pain, and unpredictable bleeding patterns.

How to ensure safe use of an estradiol patch?

You should consider the following points for the safe and effective use of an estradiol patch:

• Always wear the estradiol patch as directed by your gynaecologist or pharmacist.
• If you miss or forget to apply the patch, apply it as soon as possible.
• Do not apply more than one patch to compensate for the missed dose.
• Visit your gynaecologist for a regular follow-up for close monitoring of the progress or other possible side effects.
• Do not cut the patch without talking to your doctor first.
• Do not discontinue the use of an estradiol patch abruptly.

As a pharmacist, I would recommend patches over other dosage forms available for estradiol. Estradiol patches are often preferred over estradiol creams because creams may cause yeast infection in the vagina due to a change in vaginal pH and sensitivity.

Increased estrogen levels may also cause fluid retention. If you feel your fingers and feet are getting puffy, immediately consult your gynaecologist.

References