tretinoin

Action and Spectrum

Actions and Spectrum: 

tretinoin is a medication that belongs to the class of retinoids. It treats various skin conditions, such as acne, fine wrinkles, and hyperpigmentation. tretinoin increases cell turnover and promotes dead skin cells’ exfoliation. It also enhances collagen production, which is essential for maintaining the skin’s elasticity and firmness. 

The actions of tretinoin include: 

• Exfoliation: tretinoin promotes the shedding of dead skin cells, which helps to unclog pores and prevent the formation of acne. 
• Decreased sebum production: tretinoin helps reduce sebum production, which is the oily substance that can contribute to the development of acne. 
• Skin rejuvenation: tretinoin stimulates collagen production, which helps improve the appearance of fine wrinkles and promote a more youthful-looking complexion. 
• Hyperpigmentation: tretinoin helps to lighten areas of hyperpigmentation by promoting skin cell turnover and reducing melanin production. 

Drug Interaction

Adverse Reaction

Frequency Defined 

>10% 

Headache  

Dry mucous membranes  

Malaise  

Fever  

Bone pain  

URI  

Shivering  

Dyspnea  

Elevated liver function tests  

Hyperlipidemia  

Hemorrhage  

Infections  

Nausea and vomiting  

Leukocytosis  

Pain  

Abdominal pain  

Rash  

Peripheral edema  

DIC  

Respiratory insufficiency 

Retinoic acid-APL syndrome  

Earache  

Mucositis  

GI disorder  

Pleural effusion 

Sweating  

Anxiety  

Dizziness  

Pruritus  

Paresthesia  

Constipation  

Rales 

Depression  

Vision changes  

Dyspepsia  

Insomnia  

Alopecia  

Abdominal distension  

Skin changes  

Confusion  

Renal insufficiency  

1-10% 

Cardiac failure  

Pallor 

Cardiomyopathy  

Myocarditis  

Cardiac arrest  

Stroke  

Heart murmur  

Intracranial hypertension  

Hypotaxis  

Hemorrhage  

Facial edema  

Facial paralysis  

Spinal cord disorder  

Light reflex absent  

Seizure 

Somnolence  

Ulcer  

Cellulitis  

Enlargement of prostate  

Ascites  

Hepatosplenomegaly  

Dysuria  

Hepatitis  

Hearing loss  

Bone inflammation  

Tremor  

<1% 

Arterial thrombosis 

Myositis 

Hypercalcemia 

Pancreatitis 

Irreversible hearing loss 

Genital ulceration 

Thrombocytosis 

Venous thrombosis 

Black Box Warning

Black Box Warning: 

A chemotherapy physician should supervise the drug administration. The drug’s benefits should outweigh the potential adverse effects like retinoic acid APL syndrome, teratogenic effects, and rapidly evolving leucocytosis.

Contraindication / Caution

Contraindication/Caution: 

Some contraindications of tretinoin include: 

• Pregnancy: tretinoin is harmful to a developing fetus. Pregnant women should avoid using tretinoin or use it only under the supervision of a healthcare provider. 
• Breastfeeding: tretinoin may be excreted in breast milk and can harm nursing infants. Breastfeeding women should avoid using tretinoin or use it only under the supervision of a healthcare provider. 
• Allergy: Individuals allergic to tretinoin or its components should not use this medication. 
• Photosensitivity: tretinoin can make the skin more sensitive to sunlight, leading to sunburn and other skin damage. Patients using tretinoin should avoid prolonged sun exposure and use sunscreen with a high SPF. 

Some of the cautions associated with tretinoin use include: 

• Skin irritation: tretinoin can cause skin irritation, redness, and peeling. Patients using tretinoin should start with a low concentration and gradually increase the dosage as tolerated. 
• Interactions with other medications: tretinoin can interact with certain medications, including topical acne and oral antibiotics. Patients should inform their healthcare provider of all medications before starting tretinoin. 
• Medical conditions: tretinoin should be used cautiously in patients with eczema, rosacea, or other skin conditions that cause skin sensitivity. It should also be used cautiously in patients with a history of skin cancer. 

Pregnancy / Lactation

Pregnancy consideration:  

Category D 

Breastfeeding warnings:  

tretinoin is not recommended during breastfeeding. 

Pregnancy category: 

• Category A: Satisfactory and well-controlled studies show no risk to the fetus in the first or later trimester. 
• Category B: No evidence of risk to the fetus is found in animal reproduction studies, and there are not enough studies on pregnant women. 
• Category C: Adverse effects on the fetus found with evidence in animal reproduction studies and no adequate evidence for a human product; Pregnant women must take care of the potential risks. 
• Category D: There is adequate data with sufficient evidence of human fetal risk from various platforms. However, despite potential dangers may be used only in emergencies for potential benefits. 
• Category X: Drugs listed in this category outweigh the risks over benefits. The drug is not for pregnant women. 
• Category N: No data for the drug under this category is available. 

Pharmacology

Pharmacology: 

tretinoin is a medication that belongs to the class of retinoids. It is a vitamin A derivative available as a topical cream or gel. tretinoin binds to specific nuclear receptors in skin cells called retinoic acid receptors (RARs), which participate in gene transcription and regulation. 

When tretinoin binds to RARs, it increases the expression of genes that engage in cell growth, differentiation, and apoptosis. This leads to an increase in cell turnover, which promotes the exfoliation of dead skin cells and the formation of new skin cells. tretinoin also increases collagen and elastin production in the skin, which is essential for maintaining skin elasticity and firmness. 

tretinoin also influences sebaceous glands, which are responsible for producing sebum, an oily substance that can contribute to the development of acne. tretinoin reduces sebum production by decreasing the size and activity of the sebaceous glands. 

Additionally, tretinoin has been shown to influence the formation of melanin, the pigment responsible for skin color. It can help reduce the production of melanin, which can lead to lightening areas of hyperpigmentation. 

Pharmacodynamics: 

The main pharmacodynamic effects of tretinoin include the following: 

• Increased cell turnover: tretinoin stimulates skin cell turnover, leading to the shedding of dead skin cells and the formation of new skin cells. This effect is beneficial in treating acne and fine wrinkles, as it helps unclog pores and smooth the skin’s surface. 
• Increased collagen production: tretinoin stimulates collagen production in the skin.  Increased collagen production can help to improve the appearance of fine lines and wrinkles and can also help to firm and tighten the skin. 
• Reduced sebum production: tretinoin has been shown to reduce sebum production, an oily substance produced by the sebaceous glands. By reducing sebum production, tretinoin can help prevent acne development. 
• Decreased melanin production: tretinoin can also help to reduce the production of melanin, which is the pigment responsible for skin color. This effect is helpful in treating hyperpigmentation, as it can help lighten dark spots and even out skin tone. 

Pharmacokinetics: 

Absorption 

The peak plasma concentration is achieved in 1-2 hours. 

The peak plasma concentration is 347 ng/mL  

Distribution 

Protein-bound is 95% 

Metabolism 

The drug metabolizes by hepatic cytochrome 450. 

Metabolites formed are retinoic acid,13-cis retinoic acid, 4-oxo trans 4-oxo cis retinoic acid, and 4-oxo trans retinoic acid glucuronide. 

Elimination and Excretion 

The half-life is 0.5-2 hours. 

63% of the drug gets excreted in urine and 30% in feces

Adminstartion

Administration: 

tretinoin is typically administered topically to the skin. It is available in various formulations, including creams, gels, and solutions, with strengths ranging from 0.01% to 0.1%. The formulation and strength depend on the treated condition and the patient’s needs. 

When using tretinoin, following the instructions provided by the healthcare provider or pharmacist is essential. The medication should be applied once daily in the evening, before going to bed, to clean dry skin. The affected area should be gently cleansed and dried before applying a thin layer of the medication. The medication should be applied evenly to the affected area, avoiding the eyes, mouth, and other sensitive areas. 

It is essential to avoid excessive exposure to sunlight or artificial UV light when using tretinoin, as this can increase the risk of skin irritation and photosensitivity.  

It is also important to note that tretinoin can take several weeks or months to achieve its full therapeutic effects. Patients should continue using the medication as directed by their healthcare provider and not discontinue treatment without consulting them. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: tretinoin 

Pronounced: tre-tin-oin 

Why do we use tretinoin? 

tretinoin is used to treat a variety of skin conditions, including: 

• Acne: tretinoin is a first-line treatment for acne vulgaris. It helps to unclog pores and reduce inflammation, which can lead to the reduction of acne lesions. 
• Fine lines and wrinkles: tretinoin has been shown to improve the appearance of fine lines and wrinkles. It increases collagen production and stimulates cell turnover, leading to smoother and more youthful-looking skin. 
• Hyperpigmentation: tretinoin can be used to treat hyperpigmentation, such as dark spots or patches on the skin. It reduces melanin production, which is responsible for skin color, leading to a more even skin tone. 
• Rough skin texture: tretinoin can help improve the skin’s texture, making it smoother and softer. This effect is due to its ability to increase cell turnover and collagen production. 
• Sun damage: tretinoin can also treat skin damage caused by sun exposure. It repairs the damaged skin cells and reduces the appearance of sunspots and other signs of photodamage.