*2.1.1 Anthralin*

Anthralin via mitochondrial dysfunction might reduce the proliferation of keratinocytes and re-establish cell differentiation. As such, it is used to treat the localized plaques that are covered with thick scales localized either on body or the scalp that have failed to clear with other treatments. It is applied on the affected areas in concentration of 1%, and it is left between 20 min and 1 h before removal [26].

Among the adverse effects, the common is skin irritation or staining of the adjoining skin [25].

## *2.1.2 Coal tar*

Coal tar seems to reduce hyperproliferation of keratinocytes by supressing DNA synthesis, and it has exhibited efficacy on chronic plaque psoriasis, palmoplantar psoriasis or scalp psoriasis, improving the general aspect of the psoriasis plaque after 1 month of treatment. It appears as though the remission period of the lesions persists longer than that with other topical treatments [25].

Adverse effects number odour, staining, contact dermatitis, erythema and folliculitis.

It can be used during pregnancy, but in children caution is advertised [27].

#### *2.1.3 Salicylic acid*

Salicylic acid triggers desquamation of corneocytes via lowering intracellular cohesion between the cells of the stratum corneum. It can be applied in creams, ointments or lotions in concentrations between 2 and 6%.

The most notable adverse effect mentioned while using salicylic acid is the potential systemic intoxication [28].

It is safe to utilize during pregnancy, but in children, because of the systemic absorption, it should be avoided [25].

#### *2.1.4 Calcineurin*

Calcineurin inhibitors like tacrolimus, pimecrolimus and sirolimus supress the production of the inflammatory substances that seem accountable for the skin lesions in psoriasis. It is found in concentration of 0.3% gel or 0.5% cream [29].

As side effects, the most common is stinging sensation or contact dermatitis. It can be used in children older than 2 years old [25].

#### *2.1.5 Topical retinoids tazarotene and bexarotene*

Topical retinoids tazarotene and bexarotene downregulate the turnover by altering transcription of genes in keratinocytes upon transportation within the nucleus, after binding to retinoic acid on the cell membrane. Furthermore, it reduces the hyperproliferation of keratinocytes; it regulates the differentiation and reduces inflammation [30].

It can be applied as a cream in concentration of 0.1 and 0.05%, and when used on the nails, it seems to improve the onycholysis, pitting and salmon patches [25].

It is contraindicated during pregnancy, but it is permitted to be used in children [31].

#### *2.1.6 Topical corticosteroids*

Topical corticosteroids display immunosuppressive, anti-inflammatory, antiproliferative and vasoactive action. They are categorized based on their potency, from low-potency to very potent corticosteroids. When considering the potency and the vehicle, disease severity, patient preference and sites of lesions must be taken into account [25]. They can be found as creams, ointments, gel, solutions, nail lacquer, foams or shampoos applied on the skin, scalp or nails.

Skin atrophy, telangiectasia as well as secondary infection are the most notable side effects.

Corticosteroids can be used during pregnancy but are not recommended in children under 2 years old [32].

#### *2.1.7 Vitamin D*

Vitamin D analogues calcitriol, tacalcitol, maxacalcitol, paricalcitol and becocalcidiol decrease keratinocyte proliferation, inflammation or keratinization [33]. They can be applied on the skin, scalp or nails and are found as creams, ointments or scalp lotions.

The most common side effect is skin irritation. Very rare hypercalcemia, hypercalciuria and parathyroid hormone suppression have been described.

**91**

*2.3.2 Cyclosporine*

*Medical Management of Chronic Plaque Psoriasis in the Modern Age*

Vitamin D analogues are contraindicated in patients with hypercalcemia or in pregnancy, but they can be used in children while not exceeding the dose of 50 g/

Ultraviolets either from the sun or artificial light play a significant role in treat-

ing psoriasis mainly by supressing activated T cells, independently on the cell subpopulation involved in the disease [25]. It has been shown that NB-UVB is the most utilized phototherapeutical approach, inducing clinical and histopathological resolution of moderate-to-severe plaque psoriasis by exerting a cytotoxic effect on epidermal T cells [35, 36]. This apoptotic effect on T cells depends mostly on the penetration of the NB-UVB within the lesion, penetration that on the one hand depends on the wavelength and on the other the depth of the skin lesion [37]. Understanding that the T cells responsible for psoriasis are situated along the dermal-epidermal junction and within the epidermis, it has been determined that the optimal wavelength spectrum should range between 290 and 313 nm [38]. Currently, NB-UVB is the most common approached used worldwide, and it can be regarded as the gold

standard in therapy for treating moderate-to-severe plaque psoriasis [39].

tive, anti-inflammatory and immunosuppressive actions [40].

tions, fatigue, headaches, alopecia or oligospermia [42, 43].

theophylline, live vaccines, retinoids and azathioprine [43].

except on the day of methotrexate intake [41].

Methotrexate is a folic acid analogue employed in psoriasis for its anti-prolifera-

*Adverse effects*. In case of pregnancy, it may lead to foetal death or to teratogenic effects; also, it can be toxic to the gastrointestinal tube, liver and kidneys, and it can cause myelosuppression, malignant lymphomas, pulmonary fibrosis, severe infec-

*Laboratory tests recommended*. To start therapy with methotrexate correspondingly, the following evaluations are compulsory: physical exam, patient history, QuantiFERON-TB Gold for latent TB infection, complete blood count with differential and thrombocytes count, renal function tests, hepatic enzymes and pregnancy test. *Drug interactions*. Methotrexate has been shown to interact with cyclosporine, proton pump inhibitors, oral antibiotics, salicylates, mercaptopurine, nonsteroidal anti-inflammatory drugs, cisplatin, probenecid, phenylbutazone, sulfonamides,

As anticipated, this drug is contraindicated in pregnancy and while breastfeeding due to its teratogenic effects. Therefore, the use of contraception is highly advocated in the course of treatment. Other contraindications include blood dyscrasia,

chronic liver disease, immune deficiency syndromes or alcohol abuse [44].

Cyclosporine is a calcineurin inhibitor agent that is used in psoriasis for its immunosuppressing action and its capability to prevent the T cell proliferation

*Dosage and administration*. Methotrexate comes as a self-injectable solution administered by the patient weekly, with the added proposal of coupling with folic acid supplements. Initiation dosage is typically 10–25 mg once per week. Maximum dose should not surpass 30 mg/week. Folate intake should be about 1–5 mg daily,

*DOI: http://dx.doi.org/10.5772/intechopen.90626*

**2.2 Phototherapy in psoriasis**

**2.3 Systemic therapies**

*2.3.1 Methotrexate*

week [34].

Vitamin D analogues are contraindicated in patients with hypercalcemia or in pregnancy, but they can be used in children while not exceeding the dose of 50 g/ week [34].
