The goal of this clinical trial is to learn if topical metformin works to treat mild psoriasis vulgaris. It will also learn about the safety of topical metformin. The main questions it aims to answer are:

Does topical metformin improve psoriatic plaques in early psoriasis? What medical problems do participants have when use topical metformin? Researchers will compare topical metformin to a placebo (a look-alike substance that contains no drug) to see if topical metformin works to treat psoriasis vulgaris.

Participants will:

put topical metformin or placebo twice daily for 2 months. Visit the clinic once every months for follow up. Keep a diary of their symptoms and any side effects.

Skin biopsy will be taken from psoriatic plaque before starting treatment and another one will be taken after 2 months of starting treatment to assess the level of IL-17.

Inclusion criteria:

• Patients ≥ 18 years old
• Patients of both genders
• Patients with mild chronic plaque psoriasis ((PASI) < 10, and body surface area (BSA) < 10% and/or Dermatology Life Quality Index (DLQI) <10).

Exclusion Criteria:

• Intake of anti-psoriatic systemic therapy within the last 3 months apart from retinoids, or topical treatments within the last 2 weeks.
• Intake of systemic metformin.
• Intake of other systemic drugs that exacerbate psoriasis as anti-malarial drugs, Angiotensin- converting-enzyme inhibitors (ACEI), Ca channel blockers (CCBs) and beta blockers or intake of non-steroidal anti- inflammatory drugs (NSAID) within the last 2 weeks.
• Patients with psoriatic arthritis.
• Patients with pustular psoriasis.
• Pregnant and Lactating females.