• Alopecia
• Acniform eruptions
• Benign tumors
• Bullous diseases
• Dermoscopy
• Nevi, melanoma
• Nonmelanoma cancer
• Psoriasis and others
• Stds
• Vascular tumors
• Vulvar disease

• Acne
• Acne Psychology and Approach to Patient
• Acne Cause and Pathophysiology
• Acne Lesions and Classification
• Blackhead and Whitehead Comedone Acne
• Acne Pimples - Papules and Pustules
• Acne Pimples - Papules and Pustules
• Cystic Acne Information
• Cystic Acne Cases and Acne Scars
• Acne Treatment - How Acne Medicine Works
• Acne Treatment with Topical Antibiotics
• Acne Treatment with Topical Retinoids Retin-A
• Acne Treatment with Oral Antibiotics Doxycycline
• Acne Treatment Antiandrogens and Birth Control Pills
• Acne Treatment with Accutane Isotretinoin Part 1
• Acne Treatment with Accutane Isotretinoin Part 2
• Perioral Dermatitis
• Perioral Dermatitis Information
• Perioral Dermatitis cases
• Perioral Dermatitis Treatment
• Rosacea
• Acne Rosacea Information
• Acne Rosacea Erythema Telangiectatic
• Acne Rosacea Papulopustular
• Acne Rosacea Nose Phymatous
• Acne Rosacea Eye Ocular
• Acne Rosacea Treatment
• Hidradenitis
• Hidradenitis Suppurativa Information
• Hidradenitis Suppurativa Cases
• Hidradenitis Suppurativa Treatment

Acne Treatment with Oral Antibiotics Doxycycline

Mechanism of action

P. acne initiates inflammatory acne. The bacteria is usually present in

small numbers. P. acne proliferates in the lipid rich environment of

the microcomedo and produces proinflammatory mediators that cause

papules, pustules and cysts. P. acnes is highly sensitive to many

antibiotics. The problem is to deliver the drug into the lipid rich

environment of the microcomedo..

Topical vs. Systemic antibiotics

Moderate inflammatory acne with papules and pustules covering a wide area is treated with oral antibiotics and topical therapy. Patients

treated with an oral antibiotic may be given topical antibiotics when

the dose of the oral antibiotic is tapered.

The response to oral antibiotics is unpredictable. Some patients

respond while other do not. It is difficult to predict who will

benifit. Patients with nodular cystic acne may improve with oral

antibiotic therapy, but that response is often limited. These patients

frequently fail a course of oral antibiotics and topical therapy and

require isotretinoin.

Treatment strategy

Patients are treated with either a prolonged course or intermittent

courses of antibiotics before a complete response is achieved. Oral

antibiotics are usually given for a minimum of 1 to 3 months before the

dose is reduced. Once the appearance of new inflammatory lesions has decreased or stopped, the dose is gradually tapered then withdrawn. Topical retinoid therapy should be continued to maintain remission. Most P. acnes are sensitive to many antibiotics but less sensitive strains have appeared. Resistance to erythromycin has increased and limited the use of this drug.

Commonly used antibiotics

The most frequently prescribed antibiotics are tetracycline,

erythromycin, doxycycline, and minocycline. Clindamycin, and

trimethoprim mulfamethoxazole are very effective but are not used as

first line drugs because of their potential to cause serious side

effects. Tetracycline derived antibiotics are usually not given to

children under the age of 7 for fear of causing tooth staining.

Doxycycline, minocycline, and trimethoprim sulfamethoxazole are more lipid-soluble and therefore more effective than tetracycline and

erythromycin. P. acnes are sensitive to several antibiotics but the

prevalence of P. acnes resistant to antibiotics is increasing. Typical

starting dosages are tetracycline 500 mg bid, doxycycline 100 mg qd or bid, and minocycline 100 mg bid. All medications are available in

generic form. P. acnes is sensitive to other antibiotics such a

cephalosporins and ampicillin.

Tetracycline

Starting dose 500 mg bid

Taper dose 250 mg bid

Not taken with dairy products

GI intolerance

Photosensitivity-low incidence

Candida albicans vaginitis

Pseudotumor cerebri

Tetracycline is inexpensive. Food, particularly dairy products,

antacids, and iron interfere with the intestinal absorption. The

incidence of photosensitivity is low but increase with higher doses.

Gastrointestinal intolerance is common. Candida albicans vaginitis is a

common side effect. Pseudotumor cerebri in which the regulation of

intracranial pressure is impaired, is a rare complication. Increased

intracranial pressure causes papilledema and severe headaches.

Doxycycline

Starting dose 20, 50, 75, 100 bid

May take with food

GI intolerance

Photosensitivity

Candida vaginitis low incidence

Doxycycline is safe and commonly prescribed. It is less expensive than

minocycline. Recent evidence indicates that very low doses such as 20

mg bid may be effective . GI intolerance is common. The incidence of

photosensitivity is low but increases with increasing dose levels.

Photosensitivity reactions look like exaggerated sunburns.

Minocycline

Starting dose 50, 75, 100 bid

Most effective

May take with food

Photosensitivity-none

Vertigo dose related

Rare serious reactions

Blue-gray pigmentation

Minocycline is possibly the most effective oral antibiotic. Minocycline

is expensive but available as a generic. Photosensitivity does not

occur. It is highly lipid-soluble and penetrates the cerebrospinal

fluid, causing dose-related ataxia, vertigo, nausea, and vomiting in

some patients. Pseudotumor cerebri is rarely reported. Autoimmune

hepatitis, serum-sickness-like reactions and drug-induced lupus are

rarely reported. A blue-gray pigmentation of the skin, oral mucosa,

nails, sclera, bone and thyroid gland has been found in some patients,

usually those taking high dosages for extended periods.