These are group of broad - spectrum antibiotics polyketide antibiotic produced by the streptomyces bacterium (derived form micro-organism of a genus of Act-Inobateria); used broadly against many bacterial infection. They are group of closely related compounds that as the name implies, consist of four focused rings with a system of conjugated double bonds
ADVERSE EFFECT
Tetracyclines are generally regarded as relatively non-toxic, but they produce a fairly large number of adverse effects, some of which can be life threatening under right circumstances. Therefore, they should not be used casually.
Super infection- also known as (sprains faction) may occur with tetracylines, poarticlarly the older, ore poorly absorbed ones when given orally. Because of their broad spectrum of activity , activity against commensal organisms of the gut, and effective concentration in the gut, they nearly always alter the intestinal flora. This may occur with in 24 to 48hours, but these3 changes are not always uniically evident as diarrhea. It is not usual to find superinfection with yeasts or resistant pathogenic bacteria. Although frowned upon by the fda commercial preparation of tetracycline combined with nystatin (in oral antifungal have been parpared to help combact super infections with yeast (overgrowth of candida (rg in d vagina) or of fesistant staphy lococci (in the intestine may occur.
Indigestion- indigestion may occur for reasons already presented under the heading of superinfections. It may be difficult to differentiate indigestion due to changes in flora from that caused by direct irritation to the gastrointestinal mucosa
Direct toxicity- most direct toxicity is due to the irritant properties of the drugs, the inhibition of protein synthesis, or their predilection for bony tissues.
Deposition in calcified tissues, e.g, teeth can result in discoration,epecially when given during development stages. Higher doses given at inopportune stages of growth can result in bone deformation. Nearly every one who received tetrecyclines as a child will have teeth that fluoresce under a uv light source whether their teeth are stained brown or not.
Vestibular problems- this side effect (e.g. Dizziness/ light headedness, nausea and vomiting is commonly seen with minocycline, but not the others. This is caused by vestibular or cns toxic and is of such severity and frequency that cdc has changed recommendation on its non essential use.
Photosensitivity - severe sunburn, occurs when the patient receive a tetracycline is expose to sun or ultraviolet rays. This phototoxity is usually a problem demeclocycline, doxycycline and tetracycline.
Antianabolic effects and contraindication - antianabolic effects resulting from decreased protein synthesis. In the presence of reducing renal function, this evident as azotemia and increased serum urea nitrogen (sun) resulting to amino acid degradation.renally-impaired patients, pregnant or breast feeding women and children less than eight (8) years of age should not be treated with tetracycline.
Irritation and gastric discomfort- irritation of gastric mucosa leading to cramps or burning of the stomach can be of such severity at as to cause poor patient compliance. This often results in nausea and vomiting. Note that minocycline and doxycycline may be taken with food to reduce the impact of this irritation.
Other side effects
Fetal hepatotoxicity has been known to occur in pregnant women who received high doses of tetracycline especially if they are experiencing pyclonephritis
Pseudotumor cerebric which re benign intracranial hypertension are characterized by headache and blurred vision may occur in adults.
Sore mouth and perineal itching due to yeast are “more frequent”
Diarrhea may occur and will usually be the result of change in micro flora of the gut.
For hypersensitivity, allergic reaction is not major problem with tetracycline, although they do occur.
ADVERSE EFFECT
Tetracyclines are generally regarded as relatively non-toxic, but they produce a fairly large number of adverse effects, some of which can be life threatening under right circumstances. Therefore, they should not be used casually.
Super infection- also known as (sprains faction) may occur with tetracylines, poarticlarly the older, ore poorly absorbed ones when given orally. Because of their broad spectrum of activity , activity against commensal organisms of the gut, and effective concentration in the gut, they nearly always alter the intestinal flora. This may occur with in 24 to 48hours, but these3 changes are not always uniically evident as diarrhea. It is not usual to find superinfection with yeasts or resistant pathogenic bacteria. Although frowned upon by the fda commercial preparation of tetracycline combined with nystatin (in oral antifungal have been parpared to help combact super infections with yeast (overgrowth of candida (rg in d vagina) or of fesistant staphy lococci (in the intestine may occur.
Indigestion- indigestion may occur for reasons already presented under the heading of superinfections. It may be difficult to differentiate indigestion due to changes in flora from that caused by direct irritation to the gastrointestinal mucosa
Direct toxicity- most direct toxicity is due to the irritant properties of the drugs, the inhibition of protein synthesis, or their predilection for bony tissues.
Deposition in calcified tissues, e.g, teeth can result in discoration,epecially when given during development stages. Higher doses given at inopportune stages of growth can result in bone deformation. Nearly every one who received tetrecyclines as a child will have teeth that fluoresce under a uv light source whether their teeth are stained brown or not.
Vestibular problems- this side effect (e.g. Dizziness/ light headedness, nausea and vomiting is commonly seen with minocycline, but not the others. This is caused by vestibular or cns toxic and is of such severity and frequency that cdc has changed recommendation on its non essential use.
Photosensitivity - severe sunburn, occurs when the patient receive a tetracycline is expose to sun or ultraviolet rays. This phototoxity is usually a problem demeclocycline, doxycycline and tetracycline.
Antianabolic effects and contraindication - antianabolic effects resulting from decreased protein synthesis. In the presence of reducing renal function, this evident as azotemia and increased serum urea nitrogen (sun) resulting to amino acid degradation.renally-impaired patients, pregnant or breast feeding women and children less than eight (8) years of age should not be treated with tetracycline.
Irritation and gastric discomfort- irritation of gastric mucosa leading to cramps or burning of the stomach can be of such severity at as to cause poor patient compliance. This often results in nausea and vomiting. Note that minocycline and doxycycline may be taken with food to reduce the impact of this irritation.
Other side effects
Fetal hepatotoxicity has been known to occur in pregnant women who received high doses of tetracycline especially if they are experiencing pyclonephritis
Pseudotumor cerebric which re benign intracranial hypertension are characterized by headache and blurred vision may occur in adults.
Sore mouth and perineal itching due to yeast are “more frequent”
Diarrhea may occur and will usually be the result of change in micro flora of the gut.
For hypersensitivity, allergic reaction is not major problem with tetracycline, although they do occur.