What are Retinoids?
Retinoids are synthetic vitamin A chemical compounds, which regulate the growth of the epithelial skin cells and also affect the immune system. Retinoids play a key role in the maintenance of a relatively stable equilibrium of the immune system during an inﬂammatory response.
Acitretin or Soriatane is an oral second-generation retinoid. It is the only oral retinoid approved by the U.S. Food and Drug Administration for treating psoriasis.
How exactly Soriatane works to control psoriasis is unknown. But, in general, retinoids regulate the speed at which skin cells grow and shed.
The benefits of retinoids range from anti-inflammatory action, immunomodulatory effects (normalizing the immune system), and photoaging.
Acitretin is indicated in severe psoriasis, which has not responded to topical treatment and light treatment. It finds use in adults with severe guttate, plaque, pustular, erythrodermic, and palmoplantar psoriasis.
Other uses include:
- Skin cancers
- Other inflammatory skin disorders
- Photoaging is the term used for skin changes caused by chronic exposure to UVA and UVB light rays.
Acitretin or Soriatane is available in tablets of 10 mg and 25 mg. The attending dermatologist determines the dose of Soriatane and his decision depends on several factors including the type of psoriasis and the severity.
The prescribed dose is usually once a day with food. It is reduced once the symptoms start showing improvement and the drug is stopped when the lesions show significant improvement.
When the psoriasis symptoms reappear, you may have to start Soriatane again.
Therapeutic Effect of Retinoids
Acitretin is modestly effective against psoriasis. The action of acitretin is slow and the symptoms may worsen after starting the drug.
Though the clearance of the skin lesions is not complete, the improvement seen does justify their use.
It may take 8 to 16 weeks before you see any improvement and up to 6 months for the drug to show its peak effect.
Retinoids are more effective when used in combination with topical retinoids (corticosteroids) and phototherapy (PUVA).
Side effects of retinoids (acitretin) include:
- Dryness of mouth and the mucus membranes,
- Cracking of the lips,
- Bleeding from gums and nose,
- Increased sensitivity to sunlight,
- Itching of the skin
- Loss of hair
- Joint pains,
- Increased fat levels,
- Hepatitis, which leads to an increase in levels of liver enzymes
- Pancreatitis, which can cause abdominal pain
Retinoids are contraindicated in the following conditions
1) Allergy to retinoids
2) High triglyceride levels in the blood
3) Severely damaged liver or kidneys due to diseases
Retinoids and Pregnancy
Two pregnancy tests should test negative before starting a woman of childbearing age on retinoids (acitretin).
Acitretin or Soriatane produces serious congenital defects in the developing fetus. You should not take Soriatane for a minimum of three years before planning a pregnancy.
For the same reason, a woman must take effective birth control measures at least one month before starting acitretin to avoid getting pregnant.
Birth control pills containing only progestin may not work when on acitretin and therefore, other birth control measures should be adopted.
Again, a patient on acitretin should not donate blood for three years after having stopped this medicine as that blood could be used to transfuse a pregnant woman. Women on acitretin should avoid taking alcohol or preparations containing alcohol.
Topical Retinoid Creams
Retinoid creams or topical retinoids are used in the treatment of psoriasis, acne, and sunburnt skin.
- Tazarotene (Tazorac, Awage) cream is specifically indicated for treating moderate plaque psoriasis. It is available as Tazorac and Awage creams.
- Tretinoin is available as Retin-A cream, Atralin, Avita, and
- Adapalene is available as Differin and is used in treating acne vulgaris.
Of these, Tazarotene is the stronger form while Adapalene is the milder and less effective form of retinoid.
All these contain a compound similar to vitamin A and they act by slowing down the overproduction of the skin cells. They also reduce skin inflammation. They do this by normalizing the activity of the DNA of the skin cells.
Side effects include skin irritation and increased sensitivity to sunlight. You should apply sunscreens if you have to venture out into the sunlight after you have applied retinoid cream.
Although the risk of congenital birth defects is minimal with these topical applications, its use during pregnancy and breastfeeding is not recommended. Similarly, its use in children should be restricted.
Oral Retinoid Products
Retinoid products are also available for oral use.
- Oral Soriatane or Acitretin is specifically indicated for use in psoriasis.
- Vitamin A derivative isotretinoin is used in acne. It is marketed as Roaccutane, Accutane, Amnesteem, Sotret, Claravis, Clarus.