Hydroquinone 4% cream contains 40 mg hydroquinone per gram in a cream base of alcohol, capryloyl glycine, C13-14 isoparaffin, glycerin, glycolic acid, kojic acid, Laureth-7, lecithin, polyacrylamide, purified water, Simmondsia Chinensis (jojoba) seed oil, sodium hydroxide, squalane, and xanthan gum. It is a cream for skin bleaching. It cannot be used intraocularly; it is solely for external usage. 
It is used to lighten dark patches or spots on your skin caused by melasma, freckles, or aging. While using hydroquinone topical, it’s critical to take sun protection because this drug increases your skin’s sensitivity to the sun. Hydroquinone lightens your skin by reducing the amount of melanocytes. Melanocytes create melanin, which is responsible for your skin’s color. 
More Melanin is present in cases of hyperpigmentation due to an increase in melanocyte production. Your skin will become more evenly toned over time if you control these melanocytes. On average, it takes four weeks to take this cream effect. It may take many months of constant use to see the full benefits. If you haven’t noticed any improvement after three months of OTC use, consult your dermatologist. They may be able to offer a prescription-strength formula that is more appropriate for your needs. 
Benefits Of Hydroquinone 4% Cream:
This cream is used to lighten dark patches or spots on your skin caused by melasma, freckles, or aging.
Acne-related post-inflammatory hyperpigmentation can be just as bothersome as the acne itself. For up to 6 months, post-inflammatory hyperpigmentation can be safely treated with hydroquinone, a tyrosinase inhibitor. The effectiveness of this treatment can be increased by using a retinoid at night and a mid-potent steroid twice daily for two weeks, then only on the weekends. Combination creams aid in compliance but frequently don’t include the most potent components. When selecting a hydroquinone cream that contains a steroid, be cautious because steroids shouldn’t be used on the face for long periods. Spot therapy is helpful if post-inflammatory hyperpigmentation only comprises a few lesions. 
Ochronosis is a condition that affects the face, neck, and other photosensitive areas symmetrically with scattered and diffuse pigmentation. Histologically, it is distinguished by ochre-colored deposits in the dermis that resemble bananas. According to one case study, a 50-year-old Indian woman with evenly spaced black pigmentation on her cheeks, forehead, chin, and neck was treated with hydroquinone 4% cream. 25 years prior, she had an asymptomatic brown pigmentation across her right cheek that gradually spread to her left cheek. The study concluded that topical hydroquinone may prevent homogentisic acid oxidase from working properly in the dermis, which will lead to a localized buildup of homogentisic acid that would eventually polymerize into ochronotic pigment. 
Is It Safe To Use During Pregnancy?
Physiological changes in women during pregnancy include an increase in androgen levels. Acne vulgaris could develop or get worse as a result, and there might be more hair growth in other places of the body. Hydroquinone is used to maintain healthy skin or to improve skin appearance. 
Through the skin, hydroquinone is absorbed 35%–45.3% systemically. Topical hydroquinone 4% cream is still debatable because no evidence of retinoid embryopathy or an increased risk of significant abnormalities was discovered in 2 prospective trials that looked at its use during the first trimester of pregnancy with 96 and 106 women. Women shouldn’t be urged to take topical hydroquinone 4% cream when pregnant though until results from large studies are obtained. 
How To Use Hydroquinone 4?
Follow all usage instructions on the product’s packaging or prescribed by your doctor. Apply a small dose of this medication to unbroken skin before use, and monitor the region for any major adverse effects 24 hours later. Do not use this product and call your doctor if the test area is itchy, red, swollen, or blistering. Treatment with this product can start if there is only a slight amount of redness. Use this medication as advised by your doctor, typically twice daily, on the affected skin areas.
This procedure should only be carried out on the skin. Inappropriate use could result in undesirable skin whitening. Avoid getting this product on the inside of your nose, mouth, or eyes. If you do accidentally swallow it, rinse the region thoroughly with water. The skin’s treated areas may become more sun-sensitive as a result of this medicine. Avoid spending too much time in the sun, tanning beds, and sunlamps. Apply sunscreen and cover yourself when outside.
Possible Side Effects:
Hydroquinone is currently considered safe in the United States. There is currently no clinical evidence that suggests that hydroquinone is harmful to people.
Minor side effects, however, are still possible. It may produce an initial increase in redness or dryness, especially if you have sensitive skin. These side effects will subside as your skin adjusts to the medication.
In rare situations, hydroquinone has produced a condition known as ochronosis. It is distinguished by papules and bluish-black coloration. This might happen after a lengthy period of daily use. As a result, you should avoid using products containing this compound for more than five months at a time.
Because even a small amount of sunshine can maintain melanocytic activity, using sunscreen is an essential component of hydroquinone therapy. Sun exposure on treated skin should be avoided throughout treatment and maintenance therapy to prevent repigmentation. This can be done by wearing protective clothes or by applying a broad-spectrum sunscreen with an SPF of 15 or higher. Keep it away from your eyes and mucous membranes. Keep all medications, including this one, away from children. Call a doctor right away in the event of accidental consumption.
- Hydroquinone. Retrieved from nih.gov: https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=595dfc50-ee6f-41b5-ab5b-4c293aee342b&type=display#s4
- Shifali. Hydroquinone. Retrieved from www.goodrx.gov: https://www.goodrx.com/hydroquinone/what-is
- Vijay. Exogenous ochronosis After Prolonged Use of Topical Hydroquinone (2%) in a 50-Year-Old Indian Female. Retrieved from nih.gov: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3482806/
- Jacob. Hydroquinone Therapy for Post-inflammatory Hyperpigmentation Secondary to Acne: Not Just Prescribable by Dermatologists. Retrieved from medical journal Sweden: https://medicaljournalssweden.se/actadv/article/view/8872
- Safety of skin care products during pregnancy. Retrieved from nih.gov: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3114665/
- Topical Hydroquinone. Retrieved from www.webmd.org: https://www.webmd.com/drugs/2/drug-1347/hydroquinone-topical/details