Dermatological Pharmacology

Dermatological Pharmacology Indian Medical PG Question 1: Which of the following are treatment options for acne vulgaris?

• A. Isotretinoin
• B. All of the options (Correct Answer)
• C. Topical erythromycin
• D. Oral Minocycline

Dermatological Pharmacology Explanation: ***All of the options*** - All listed options (Isotretinoin, Topical erythromycin, and Oral Minocycline) are well-established and commonly used **treatment options for acne vulgaris**, depending on the severity and type of acne. - The choice of treatment often follows a stepped approach, starting with topical agents for mild to moderate acne and progressing to oral medications like antibiotics or isotretinoin for more severe or resistant cases. *Isotretinoin* - **Isotretinoin** is a powerful oral retinoid primarily used for **severe, recalcitrant nodular acne** that has not responded to other treatments. - It works by reducing sebum production, follicular hyperkeratinization, inflammation, and the growth of *P. acnes*. *Topical erythromycin* - **Topical erythromycin** is an **antibiotic** used to treat mild to moderate inflammatory acne by reducing the growth of *Cutibacterium acnes* (formerly *Propionibacterium acnes*) and decreasing inflammation. - It is often combined with other topical agents like benzoyl peroxide to minimize the development of **antibiotic resistance**. *Oral Minocycline* - **Oral minocycline** is a **tetracycline antibiotic** used for moderate to severe inflammatory acne. - It reduces bacterial populations on the skin and exhibits **anti-inflammatory properties**, making it effective for widespread or deeper lesions.

Dermatological Pharmacology Indian Medical PG Question 2: A 24-year-old woman presents with multiple nodular, cystic, and pustular lesions on her face and shoulders for 2 years. What is the drug of choice for her treatment?

• A. Isotretinoin (Correct Answer)
• B. Azithromycin
• C. Doxycycline
• D. Acitretin

Dermatological Pharmacology Explanation: ***Isotretinoin*** - This patient presents with **severe nodulocystic acne**, characterized by multiple nodular, cystic, and pustular lesions, which is the primary indication for oral isotretinoin. - Isotretinoin is a potent systemic retinoid that **reduces sebum production**, inhibits _Propionibacterium acnes_, normalizes keratinization, and has anti-inflammatory effects, leading to significant and often long-term remission. *Azithromycin* - Azithromycin is an **antibiotic** that can be used for inflammatory acne, but it is typically reserved for patients who cannot tolerate or are resistant to other tetracycline-class antibiotics. - While it has anti-inflammatory properties, it is generally **less effective for severe nodulocystic acne** compared to isotretinoin. *Doxycycline* - Doxycycline is a **tetracycline antibiotic** commonly used for moderate to severe inflammatory acne due to its anti-inflammatory effects and ability to reduce _P. acnes_ bacteria. - However, for **severe nodulocystic acne**, systemic antibiotics like doxycycline are often insufficient as monotherapy and **isotretinoin is the preferred treatment** for its superior efficacy in such cases. *Acitretin* - Acitretin is a systemic retinoid primarily used for **severe psoriasis** and other keratinization disorders. - It is **not indicated for the treatment of acne** and has a different safety profile and mechanism of action compared to isotretinoin.

Dermatological Pharmacology Indian Medical PG Question 3: Steroids are used in the Rx of the following diseases EXCEPT:

• A. Pemphigus vulgaris
• B. Chronic fungal infection (Correct Answer)
• C. Erythema multiforme
• D. Contact dermatitis

Dermatological Pharmacology Explanation: ***Chronic fungal infection*** - **Steroids are absolutely contraindicated** in **chronic fungal infections** as they **suppress cell-mediated immunity**, leading to worsening of the infection and potential dissemination. - Corticosteroids promote fungal growth and can convert a localized infection into a systemic, life-threatening condition. - This is the **clearest contraindication** among the options. *Pemphigus vulgaris* - **Pemphigus vulgaris** is an **autoimmune blistering disease** where **high-dose systemic steroids are the first-line treatment**. - Corticosteroids (1-2 mg/kg/day of prednisolone) are essential for controlling autoantibody production and preventing life-threatening complications. - **Steroids are clearly indicated**, not contraindicated. *Erythema multiforme* - **Erythema multiforme** is typically a **self-limiting condition** managed primarily with **supportive care** (antipyretics, antihistamines, topical care). - **Systemic steroids are generally NOT recommended** as standard treatment and their use remains **controversial**. - However, in very rare severe cases with extensive mucosal involvement, some clinicians may consider a short course, making this **not an absolute contraindication** like fungal infections. *Contact dermatitis* - **Contact dermatitis** is commonly treated with **topical corticosteroids** as first-line therapy to reduce inflammation and pruritus. - In severe, widespread cases, a short course of **oral steroids** may be prescribed. - **Steroids are clearly indicated** for this condition.

Dermatological Pharmacology Indian Medical PG Question 4: All of the following are used in systemic therapy of psoriasis except

• A. Methotrexate
• B. Cyclosporine
• C. Oral glucocorticoids (Correct Answer)
• D. Acitretin

Dermatological Pharmacology Explanation: ***Oral glucocorticoids*** - **Oral glucocorticoids** are generally avoided in psoriasis because they can precipitate severe **rebound flares** upon discontinuation or during dose tapering. - While they can temporarily suppress inflammation, the risk of worsening psoriasis and other systemic side effects makes them unsuitable for long-term systemic therapy. *Methotrexate* - **Methotrexate** is a commonly used systemic agent for psoriasis due to its **immunosuppressive** and **anti-proliferative effects**, targeting rapidly dividing cells. - It works by inhibiting dihydrofolate reductase and is typically given once weekly for chronic plaque psoriasis. *Cyclosporine* - **Cyclosporine** is an effective systemic immunosuppressant used for severe, resistant psoriasis, particularly when rapid control is needed. - It primarily acts by inhibiting **T-cell activation** and proliferation, thereby reducing the inflammatory response in psoriasis. *Acitretin* - **Acitretin** is an oral retinoid derivative of vitamin A, used in severe forms of psoriasis, especially **pustular** and **erythrodermic** types. - It works by modulating **keratinocyte differentiation** and proliferation, helping to normalize skin cell growth.

Dermatological Pharmacology Indian Medical PG Question 5: Recalcitrant acne is treated by:

• A. Steroids
• B. Retinoids (Correct Answer)
• C. Oral erythromycin
• D. Oral tetracycline

Dermatological Pharmacology Explanation: ***Retinoids*** - **Oral retinoids**, particularly **isotretinoin**, are highly effective for **recalcitrant, severe acne** that has not responded to conventional therapies. - They work by reducing **sebum production**, inhibiting **Propionibacterium acnes**, normalizing **follicular keratinization**, and possessing **anti-inflammatory** properties. *Steroids* - **Systemic steroids** are generally not used for long-term acne treatment due to significant side effects and the potential for **steroid-induced acne**. - They may be used short-term for **severe nodulocystic acne** with significant inflammation, but not as a primary treatment for recalcitrance. *Oral erythromycin* - **Oral erythromycin** is an antibiotic sometimes used for acne, but resistance is common, limiting its effectiveness, especially in **recalcitrant cases**. - It primarily targets **Propionibacterium acnes** and has some **anti-inflammatory** effects, but is less potent than retinoids for severe, persistent acne. *Oral tetracycline* - **Oral tetracyclines** (e.g., doxycycline, minocycline) are commonly used for moderate to severe acne, but if acne is **recalcitrant**, it indicates a lack of response to these antibiotics. - Their mechanism involves reducing **bacterial growth** and inflammation, but they do not address the underlying pathogenesis of severe acne as comprehensively as retinoids.

Dermatological Pharmacology Flashcard 1 of 5

Question: Baseline evaluation of serum lipids, transaminases, and CBC should be done before starting any systemic _____

Answer: retinoids

Dermatological Pharmacology Flashcard 2 of 5

Question: Papulopustular rosacea is treated with topical _____

Answer: metronidazole

Dermatological Pharmacology Flashcard 3 of 5

Question: _____ is a characteristic cutaneous reaction to treatment with bleomycin

Answer: Flagellate hyperpigmentation/flagellate erythema

Dermatological Pharmacology Flashcard 4 of 5

Question: First line rx for oral lichen planus is _____ ointment, soluble prednisolone/betamethasone tablets (for mouthwash) and oral prednisolone (for severe erosive disease)

Answer: clobetasol propionate

Dermatological Pharmacology Flashcard 5 of 5

Question: Patients taking 5FU as a topical cream can have complications of a _____ called Serpentine Supravenous Pigmentation

Answer: hyperpigmentation reaction