Photosensitivity, tetracyclines causing

Tetracyclines cause photosensitivity and exposure to sunlight is thus contraindicated. 

Photosensitivity Tetracyclines, especially demeclocycline, may cause enhanced skin sensitivity to ultraviolet light. 

Tetracyclines are used as alternative dnigs in a variety of circumstances when the patient is unable to take the dnig of choice, eg, in patients allergic to penicillin (88,89). Tetracyclines are widely known to cause staining of teeth (and are therefore contra-indicated in children developing permanent teeth), photosensitivity, and, in the case of minocycline, vestibular toxicity. Details of these adverse effects and others associated with administration of tetracyclines have been comprehensively reviewed (96—101). 

Sulfacetamide Prednisolone (Blephamide, Others) [AntibiotiC/ Anti-inflammatory] Uses Steroid-responsive inflammatory ocular conditions w/ Infxn or a risk of Infxn Action Antibiotic anti-inflammatory Dose Adults Feds >2 y. Apply oint lower conjunctival sac daily-qid soln 1-3 gtt 2-3 h while awake Caution [C, /-] Sulfonamide sensitivity age <2 mo Disp Oint, susp SE Irritation, burning, blurred vision, brow ache, Stevens-Johnson synd, photosens Interactions T Effects W/ tetracyclines EMS T Risk of photosensitivity Rxns OD Unlikely to cause life-threatening Sxs... 

A patient is admitted with what looks like extensive first degree burns over nearly the whole body. These have occurred since the patient had been on holiday. You diagnose sunburn and get into a debate with the patient who claims to have been very careful and has never had such a problem before. What you have missed is that the patient had an ear infection on the flight, which caused pain, went to a local doctor and was given tetracycline-a well known cause of photosensitivity. 

Demeclocycline has a spectrum of activity comparable to tetracycline but it may cause nephrogenic diabetes insipidus. It is also associated with a high incidence of photosensitivity. 

Tetracycline Prevents bacterial protein synthesis by binding to the 30S ribosomal subunit Bacteriostatic activity against susceptible bacteria Infections caused by mycoplasma, chlamydiae, rickettsiae, some spirochetes malaria H pylori acne Oral mixed clearance (half-life 8 h) dosed every 6 h divalent cations impair oral absorption Toxicity Gastrointestinal upset, hepatotoxicity, photosensitivity, deposition in bone and teeth... 

Doxycydine (Adoxa, Periostal-, Oracea, Vibramycin, Vibra-Tabs) [Anribiotic/Tetracycline] Uses Broad-spectrum antibiotic acne vulgaris, uncomplicated GC, Chlamydia sp, PID, Lyme Dz, skin Infxns, anthrax, malaria prophylaxis Action Tetracycline bacteriostatic X- protein synth Dose Adults. 100 mg PO ql2h on 1st d, then 100 mg PO daily bid or 100 mg IV ql2h acne daily dosing, Chlamydia 7d, Lyme Dz 14—21 d, PID 14 d Peds >8 y 5 mg/kg/24 h PO, to a max of 200 mg/d - daily-bid Caution [D, +] Hepatic impair Contra Children <8 y, severe hepatic dysfxn Disp Tabs, caps, syrup, susp, inj SE D, GI disturbance, photosens Interactions T Effects OF digoxin, warfarin 1 effects W/ antacids, Fe, barbiturates, carbamazepine, phenytoins, food 4-effects OF penicillins EMS Monitor for signs of electrolyte disturbances and hypovolemia d/t D monitor for S/Sxs of super Infxn T risk of photosensitivity Rxns antibiotic of choice for the Tx and prophylaxis of anthrax exposure expired tetracyclines have been known to cause nephrotox OD May cause adverse GI effects symptomatic and supportive... 

Gastrointestinal distress (nausea, vomiting, diarrhea) may be a problem with tetracycline use. Hypersensitivity reactions (such as rashes) may also occur, as well as an increase in skin sensitivity to ultraviolet light (photosensitivity).16 Tetracyclines form chemical complexes with calcium that may impair the growth and development of calcified tissues such as bone and teeth, especially in children.69 Tetracyclines also cause discoloration of teeth in children and pregnant women, apparently because of the tetracycline-calcium interaction.69 As mentioned previously, development of tetracycline-resistant strains and resulting superinfections may be a serious problem during tetracycline therapy. 

Before the introduction of specific vasopressin receptor antagonists, pharmacological treatments for hyponatremia centered on the use of loop diuretics and nonspecific inhibitors of vasopressin signaling, such as lithium carbonate and demeclocycline.11 The utility of such therapies has been limited by a range of sideeffects. Loop diuretic use can result in electrolyte imbalances and suffers from poor response predictability.11 Lithium carbonate suffers from a low therapeutic index and a risk of renal damage as well as limited effectiveness in many patients. Lithium carbonate has therefore been nearly completely supplanted by demeclocycline, a tetracycline antibiotic, in the treatment of chronic hyponatremia.12 Demeclocycline use is itself limited by its nephrotoxicity (particularly in cirrhotic patients), ability to cause reversible uremia, and ability to induce photosensitivity.1,11... 

The retinal lesions caused by direct visual sun exposure are similar to those caused by less direct ultraviolet light, as well as by mild but repeated solar interactions over many years, which occur in many of the elderly. In addition, the recent diminishing level of atmospheric ozone may add to these problems, especially in the future if its concentration continues to diminish. Moreover, numerous drugs, including phenothiazines, tetracycline, and allopurinol, are photosensitizers, which may further add to the problem in some individuals. 

Doxycycline can cause nausea, vomiting, and diarrhea. The bioavailability of doxycycline is reduced if coadministered with multivalent ions such as iron or magnesium. However, unlike tetracycline, it can be administered with food and dairy products. In addition, patients taking tetracyclines may experience photosensitivity, especially if they are fair skinned. Patients taking tetracyclines should avoid prolonged exposure to sunlight. 

Another effect of coal tar creosote exposure that could be affected by interaction with other chemicals is photosensitivity. Certain pharmaceutical agents (e.g., tetracycline) that, in and of themselves, cause photosensitivity whose action may be synergistic with that of coal tar creosote or coal tar. 

The systentic administration of demeclocycline elicits photosensitization to ultraviolet light or sunlight. Minocycline causes vertigo and dizziness. The intravenous adntinistration of tetracyclines has been observed to cause venous thrombosis. 

Gastrointestinal reactions that may occur during tetracycline administration include nausea, vomiting, diarrhea, epigastric distress, stomatitis, and sore throat. Skin rashes also may be seen. A photosensitivity (phototoxic) reaction may be seen witli tliis group of dni, manifested by an exa rated sunburn reaction when the skin is exposed to sunlight even for brief periods. Demeclocychne seems to cause the most serious photosensitivity reaction, whereas minocycline is least likely to cause this type of reaction. 

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