Understanding the Uses and Side Effects: What Does TAC Cream Do?

October 8, 2025 •

4 min read

Topical tacrolimus, often called TAC cream, is a non-steroidal prescription medication used to treat moderate to severe eczema (atopic dermatitis) [1.4.3]. So, what does tac cream do? It works by suppressing the skin's immune system to reduce inflammation, itching, and redness [1.2.1].

Quick Summary

TAC cream, a topical calcineurin inhibitor known as tacrolimus, treats skin conditions like eczema by weakening the skin's immune response. It is a second-line therapy used when other treatments fail [1.2.3, 1.2.1].

Key Points

What it is: TAC cream (tacrolimus) is a non-steroidal, topical calcineurin inhibitor used to treat skin conditions [1.2.1].
Primary Use: It's a second-line treatment for moderate to severe atopic dermatitis (eczema) when other therapies fail [1.2.3].
Mechanism: It works by weakening the skin's immune system to reduce inflammation, itching, and redness [1.2.1].
Strengths: Available in 0.03% (for children 2-15) and 0.1% (for adults) ointment formulations [1.9.3, 1.9.2].
Advantage Over Steroids: Unlike topical corticosteroids, it does not cause skin thinning (atrophy), making it safer for the face and skin folds [1.7.1].
Black Box Warning: The FDA requires a warning about a rare, potential risk of skin cancer and lymphoma with long-term use [1.5.1].
Sun Protection: Users must avoid or limit sun exposure and use sunscreen on treated areas [1.10.1].
Common Side Effects: The most common side effects are temporary stinging, burning, or itching at the application site [1.2.1].

What is TAC Cream (Tacrolimus)?

TAC cream is the common name for topical tacrolimus, a prescription ointment sold under brand names like Protopic® [1.4.2]. It belongs to a class of drugs called topical calcineurin inhibitors (TCIs) [1.2.1]. This medication is not a steroid. It's primarily used as a second-line treatment for moderate to severe atopic dermatitis (eczema) when other medications, such as topical corticosteroids, are ineffective or not advisable [1.4.3, 1.2.3]. Tacrolimus is available in two strengths: 0.03% and 0.1% [1.9.2]. The 0.03% strength is approved for children aged 2 to 15, while adults can use either strength [1.9.3].

How Does It Work?

The primary function of TAC cream is to modulate the body's immune response in the skin. Eczema is an allergic-type condition characterized by an overactive immune system response that leads to inflammation, redness, and itching [1.2.1]. Tacrolimus works by inhibiting calcineurin, a protein that activates T-cells, which are a type of immune cell [1.3.3, 1.3.4]. By binding to a specific protein within these T-cells, it blocks the production and release of inflammatory cytokines—substances that cause the symptoms of eczema [1.3.1, 1.3.2]. This action weakens the skin's immune defense system, thereby decreasing the allergic reaction and relieving the eczema symptoms [1.2.1].

Primary Uses and Applications

Atopic Dermatitis (Eczema) The most common use for tacrolimus ointment is treating moderate to severe atopic dermatitis [1.4.3]. It is particularly beneficial for sensitive skin areas where topical steroids could cause skin thinning (atrophy), such as the face, eyelids, and skin folds [1.7.1, 1.3.3]. It's typically applied as a thin layer to the affected areas twice daily [1.6.2]. Treatment should continue until the signs and symptoms of eczema clear up and can be restarted if symptoms reappear, but it is not intended for continuous long-term use [1.2.1].

Off-Label Use: Vitiligo Tacrolimus is also used off-label to treat vitiligo, a condition that causes the loss of skin color in patches [1.8.4]. Its immunomodulatory effects can help in the repigmentation process, especially on the head and neck [1.8.3]. Studies have shown that combining tacrolimus with phototherapy (like narrow-band UVB) can be an effective treatment for non-segmental vitiligo [1.8.4]. In March 2024, France authorized its use for vitiligo through a compassionate prescription framework [1.8.2].

How to Properly Apply TAC Cream

Correct application is crucial for the medication's effectiveness and safety:

Wash Hands: Always wash your hands with soap and water before and after application, unless your hands are the treatment area [1.6.2].
Ensure Skin is Dry: Apply the ointment to clean, completely dry skin [1.6.3].
Apply a Thin Layer: Use the smallest amount necessary to cover the affected skin with a thin layer. Rub it in gently and completely [1.6.2].
Avoid Washing Off: Do not bathe, shower, or swim immediately after applying the ointment, as this can wash it off [1.6.2].
No Occlusive Dressings: Do not cover the treated skin with bandages or wraps unless directed by a doctor [1.6.2]. Normal clothing is fine.
Moisturizers: If you use moisturizers, apply them after applying tacrolimus ointment [1.10.4].

Comparison with Topical Corticosteroids


Feature	Tacrolimus (TAC Cream)	Topical Corticosteroids
Mechanism	Calcineurin inhibitor; suppresses T-cell activation [1.3.3].	Anti-inflammatory; constricts blood vessels.
Primary Use	Second-line for moderate-to-severe eczema [1.2.3].	First-line for many inflammatory skin conditions [1.7.1].
Side Effects	Main side effect is skin burning/stinging, which usually subsides [1.2.2]. Carries a black box warning for a theoretical cancer risk [1.5.1].	Long-term use can cause skin atrophy (thinning), striae, and telangiectasia [1.7.1].
Use on Face/Folds	Considered safer for long-term use on sensitive areas as it does not cause skin atrophy [1.7.1, 1.3.3].	Use of potent steroids is often limited in these areas due to the risk of atrophy [1.7.1].
Efficacy	0.1% strength has similar effectiveness to moderate-to-high potency corticosteroids [1.7.1].	Potency varies widely, from mild to super-potent [1.7.4].

Important Safety Information and Side Effects

Black Box Warning The U.S. Food and Drug Administration (FDA) has issued a boxed warning for tacrolimus. This is the most serious warning from the FDA [1.5.1]. It notes that a small number of people using TCIs have developed cancers like lymphoma and skin cancer, although a direct causal link has not been established [1.5.1, 1.5.2]. Due to this theoretical risk, tacrolimus is recommended for short-term, intermittent use and not for continuous long-term application [1.10.4].

Common Side Effects The most frequent side effects occur at the application site and are usually temporary [1.10.2]:

Skin burning, stinging, or itching, especially during the first few days of treatment [1.2.1].
Skin redness [1.5.3].
Increased skin sensitivity to hot or cold temperatures [1.2.1].

Other potential side effects include flu-like symptoms, headache, acne, and swollen hair follicles [1.2.1, 1.5.5].

Precautions

Sun Exposure: Patients should minimize or avoid natural and artificial sunlight (tanning beds, UV light therapy) on treated areas. Use sunscreen and protective clothing when outdoors [1.10.1, 1.6.2].
Alcohol: Drinking alcohol while using tacrolimus may cause the skin or face to become flushed and feel hot [1.10.5].
Weakened Immune System: This medication should not be used by individuals with a weakened immune system [1.10.5].
Infections: Do not apply to areas with active viral or bacterial skin infections [1.5.3].

Conclusion

So, what does TAC cream do? It serves as a valuable non-steroidal treatment for inflammatory skin conditions, most notably atopic dermatitis, by suppressing the local immune response. While it offers a significant advantage over steroids by not causing skin atrophy, making it suitable for sensitive areas, its use requires careful consideration of the potential risks outlined in its black box warning. Patients should always use tacrolimus exactly as prescribed by their healthcare provider, be vigilant about sun protection, and report any unusual symptoms or lack of improvement after 6 weeks of treatment [1.2.1].

For more detailed information, consult the FDA Medication Guide for Protopic®.

Frequently Asked Questions

No, TAC cream (tacrolimus) is not a steroid. It belongs to a class of drugs called topical calcineurin inhibitors, which work by suppressing the immune system in the skin [1.2.1, 1.7.1].

The main use is to treat moderate to severe atopic dermatitis (eczema) in patients who have not responded well to other medications, like topical steroids [1.4.3].

Improvement in eczema symptoms can often be seen within the first few weeks of treatment. However, if your condition does not improve after 6 weeks, you should consult your doctor [1.2.1].

Yes, tacrolimus is often preferred for sensitive areas like the face because it does not cause skin thinning (atrophy), a common side effect of long-term steroid use [1.7.1].

A burning or stinging sensation is a common side effect, especially during the first few days of treatment. This usually happens as your skin is adjusting to the medication and typically subsides as the skin heals [1.2.1, 1.5.5].

The FDA issued a black box warning due to rare cases of skin cancer and lymphoma reported in people who used tacrolimus. A direct link has not been proven, but it is recommended to use the medication for short, intermittent periods and not continuously long-term [1.5.1, 1.10.4].

You should limit or avoid sun exposure, including sunlamps and tanning beds, while using tacrolimus. Always wear protective clothing and use sunscreen on treated areas when outdoors [1.10.1, 1.6.2].