Brief Answer:
Sun protection; topical tretinoin; Oral Antioxidant capsules

Detailed Answer:
Hello. Thank you for writing to us

I have gone through your query and I have noted down your concern.

Ageing comprises both chronological ageing (natural ageing) and photoageing (sun induced ageing).
Skin ageing manifests as fine lines, wrinkles, looseness of skin etc which is primarily due to degradation of collagen and elastin fibres, present in dermis.

Therefore steps to slow down skin ageing include sun protection and stimulation of synthesis of new collagen and elastin.

Sunnscreen/ sun protection is the single most effective measure against ageing.
You must use a broad spectrum sunscreen throughout the day to protect you skin from damaging UV A and UV B rays present in solar specturm.
A broad spectrum sunscreen protects against both UVA as well as UVB portion of the electromagnetic spectrum e.g a sunscreen with spf 50 would be adequate.
A lot of good sunscreen brands are available e.g Sebamed sunscreen Or Neutrogena ultrasheer sunscreen.
Reapply sunscreen every 2-3 hours, on all exposed skin, specially when outdoors.
The quantity of sunscreen that should be applied for each application is 3 ml for each arm and 3 ml for face and neck.

At night you may use a tretinoin 0.025% cream (e.g retino-A 0.025%) cream over cheeks, forehead (sparing angles of mouth and corners of eyes). It is the most effective and the most economical antiageing ingredient.
Topical tretinoin prevents or delays and even reverses signs of ageing, if used regularly. Mechanism of action of tretinoin is stimulation of synthesis of new collagen which will helps fill fine lines and delays wrinkles.
Tretinoin is a minor irritant and therefore some people may experience minor redness peeling of skin specially during the early part of therapy. A dermatololgist will usually tell this beforehand.
One way to prevent these side effects is to initially use it every alternate days or once every third day till your skin gets used to it and thereafter once daily at night.

Orally you may take an antioxidant capsule once daily e.g capsule Antoxid-HC or Derantox.
The rationale behind oral antioxidants as antiageing is because UV A induces free radicals and reactive oxygen in skin which degrades collagen. Antioxidants scavanges free radicals and reactive oxygen species and therefore prevents damage to skin.

Besides tretinoin, glycolic acid (alpha hydroxy acids), topical vitamin C ( available as 10% - 20% serum) is also antiageing.

These are prescription medications and should be used under supervision of a dermatologist, therefore I suggest that you visit a dermatologist in your region for the needful.

Regards

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