New Perspectives on Antiacne Plant Drugs: Contribution to Modern Therapeutics

Table 1

An overview of available therapies for acne and associated factors.

Class	Drug	Dose	Mode of action	Clinical evidence	Adverse effects	Reference
Retinoids	Tretinoin	0.01–0.05%	Anti comedogenic effect, indirect antimicrobiotic effect; anti-inflammatory, ability to regulate keratinocyte desquamation	Mild comedonal acne	Low grade irritant dermatitis with erythema and scaling, burning, photosensitivity	[4, 34–38, 42]
	Isotretinoin	1.0–2.0 mg/kg/day	Inhibits sebaceous gland differentiation and proliferation, reduces sebaceous gland size, suppresses sebum production, normalizes follicular epithelial desquamation, regulates keratinocyte—keratinocyte adhesion, antiinflammatory effect	Severe recalcitrant; nodular acne	Cheilitis, conjunctivitis, hyper triglyceridemia, elevated serum cholesterol levels and liver enzymes, blood dyscrasias, dry eyes and mouth, photosensitivity, and pruritus; incidence/risk of teratogenicity, myalgia, arthralgia, headaches, malaise, mood swings and depression; acne fulminans, characterized by extensive erosive lesions, fever, arthralgias, leukocytosis premature epiphyseal closure in young children, asthma exacerbation, skin fragility, spectrum of ophthalmological disturbances, from dry eyes to optic neuritis
	Adapalene	0.1%–0.3%	Anti comedogenic effect, indirect antimicrobiotic effect	Mild to moderate; comedonal acne	Irritation, contraindicated in pregnant women
	Tazarotene	0.05% or 0.1%
	Retinol	0.04%–0.07%			Photosensitivity, xerosis, cheilitis
Keratolytics	Azelaic acid	20%	Anticomedogenic and antimicrobial effect, reduces the production of keratohyalin granules in the pilosebaceous duct and thus normalizes the ductal hypercornification; keratolytic and anti-inflammatory	Mild to moderate acne	Only a slight sensation of burning or tingling, mild erythema	[34–36, 42]
	Benzoyl peroxide	1%–10%	Antimicrobial effect (reactive oxygen species are generated that kill bacteria by oxidizing constituents of their cell membranes), antiinflammatory, very mild anti comedogenic effects, keratolytic	Inflammatory acne,; Mild to moderate acne	Irritant dermatitis with erythema and scaling, dryness, peeling, stinging, or burning, bleach hair, clothes, and bed linens
	Salicylic acid	2%	Anti-inflammatory, topical desquamating agent, comedolytic	Comedonal acne	Peeling, hyperpigmentation, toxic inner ear damage, hypoglycemia, hypersensitivity, acute salicylate intoxication	[36, 37]
	Sulfur	1–10%	Keratolytic activity		Malodor and dry skin
	Zinc	200 mg/day (Zn gluconate), 400 or 600 mg/day (Zn sulfate )	Bacteriostatic, inhibits chemotaxis, and may decrease tumor necrosis factor—α production	Mild or moderate acne, severe and inflammatory acne	Nausea, vomiting, and diarrhoea with gastrointestinal side effects
	Alpha hydroxyl acids (Glycolic and lactic acid)	10%	Exfoliative capabilities, promotes epidermolysis, disperse basal layer melanin, increases collagen synthesis within the dermis
	Sodium sulfacetamide	10% with 5% sulphur	Inhibiting P. acnes proliferation, act through competitive antagonism of para-aminobenzoic acid, halting bacterial DNA synthesis	Inflammatory lesions and; comedones	Mild transient dryness, itching
Antibiotics	Erythromycin	2%–4%	Antimicrobial effect, a significant decrease of free fatty acids of the skin surface lipids, as a marker of P. acnes lipase activity, indirect anticomedogenic effect, suppress leukocyte chemotaxis and bacterial lipase activity	Moderate to severe; inflammatory acne	Bacterial resistance and cross resistance	[4, 34–36, 38, 42]
	Clindamycin	1%	Antibacterial, anti-inflammatory	Inflamed lesions	Antibiotic resistance, diarrhoea, pseudomembranous colitis
	Tetracycline	500 to 1000 mg/day	Suppress leukocyte chemotaxis and bacterial lipase activity	Moderate to severe inflammatory acne	Drug-induced lupus erythematous or a dose-duration pigmentation, abdominal colic, diarrhoea and vaginal candidiasis, enamel hypoplasia and a yellowish discoloration of the forming teeth, gastrointestinal discomfort, less commonly, photosensitivity, esophagitis, pancreatitis and pseudo-porphyria
	Minocycline	75–200 mg/day	Inhibits cytokines and matrix metalloproteinases thought to contribute to inflammation and tissue breakdown	Mild papulopustular acne	Urticaria to drug induced lupus, vertigo, dizziness, ataxia, and rarely a bluish discoloration of the skin, autoimmune hepatitis, hyper sensitivity syndrome
	Doxycycline	50 to 100 mg twice Daily			Photosensitivity reactions, gastrointestinal disturbances
	Trimethoprim/; Sulfamethoxazole		Anti-inflammatory effect, antibacterial, blocks dihydrofolate reductase/dihydropteroate synthetase, which ultimately diminishes bacterial purine and pyrimidine synthesis		Thrombocytopenia, agranulocytosis anemia, hypersensitivity
Hormonal therapy	Spironolactone	50–100 mg/day	Androgen receptor blocker, which decreases androgen-stimulated sebocyte proliferation, inhibit androgen biosynthesis by decreasing type II 17α-hydroxysteroid dehydrogenase, therefore halting the conversion of androstenedione to testosterone, inhibition of 5 α-reductase and increased steroid-hormone binding globulin together resulting in 30–50% reduction in sebum excretion	Moderate acne in women	Hyperkalemia, diuretic effect, dysmenorrhea, dysphoria, breast tenderness menstrual irregularities, lethargy, headache, lightheadedness, dizziness, orthostatic hypotension, gynaecomastia in men	[35, 38, 38, 40]
	Flutamide	250–500 mg/day	Converted to its highly potent metabolite, 2-hydroflutamide, which acts to selectively inhibit the binding of dihydrotestosterone to the androgen receptor		Hepatotoxicity and GIT disturbances, hot flashes, and decreased libido
	Cyproterone acetate	50–100 mg/day	Reduce sebum production, comedogenesis		Hepatotoxicity, breast tenderness, headache, nausea, breakthrough bleeding
	Ethinyl estradiol	20–35 µg	Reduce the production of androgens and sebum by inhibiting LH and FSH, thereby suppressing ovulation and ovarian androgen production, increasing sex hormone binding globulin and by decreasing levels of freely circulating testosterone and inhibit ovarian androgen production		Nausea, mood changes, contraindications to using OCs in an otherwise healthy woman include smoking, migraine headaches with aura and hypertension
	Norgestimate, Norethindrone, Drospirenone	35 𝜇g	Suppress ovarian androgens and reduce bioavailable testosterone by an estrogen-mediated increase in steroid hormone binding globulin
	prednisone	2.5 to 5 mg/d	Adrenal androgen-production blockers