Tetracon Side Effects
Generic name: tetracycline
Medically reviewed by Drugs.com. Last updated on Oct 18, 2022.
Note: This document contains side effect information about tetracycline. Some dosage forms listed on this page may not apply to the brand name Tetracon.
Applies to tetracycline: capsule, capsule extended release, powder for suspension, syrup, tablet, tablet delayed release, tablet extended release.
Serious side effects of Tetracon
Along with its needed effects, tetracycline (the active ingredient contained in Tetracon) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor as soon as possible if any of the following side effects occur while taking tetracycline:
For all tetracyclines
- Increased sensitivity of skin to sunlight (rare with minocycline)
- Abdominal pain
- bulging fontanel (soft spot on head) of infants
- loss of appetite
- nausea and vomiting
- visual changes
- yellowing skin
For demeclocycline only
- Greatly increased frequency of urination or amount of urine
- increased thirst
- unusual tiredness or weakness
For minocycline only
- Pigmentation (darker color or discoloration) of skin and mucous membranes
Other side effects of Tetracon
Some side effects of tetracycline may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.
Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
For all tetracyclines
- Cramps or burning of the stomach
- Itching of the rectal or genital (sex organ) areas
- sore mouth or tongue
For minocycline only
- Dizziness, light-headedness, or unsteadiness
In some patients tetracyclines may cause the tongue to become darkened or discolored. This effect is only temporary and will go away when you Stop taking tetracycline.
For Healthcare Professionals
Applies to tetracycline: compounding powder, oral capsule, oral suspension, oral tablet.
Gastrointestinal side effects have included anogenital lesions with monilial overgrowth, anorexia, black hairy tongue, dysphagia, enamel hypoplasia, enterocolitis, epigastric distress, diarrhea, glossitis, nausea, permanent tooth discoloration, and vomiting. Rarely, esophageal ulceration has been reported with oral tablets and capsules.[Ref]
There have been several cases of esophageal ulcers associated with oral tetracycline therapy. In each case, the patient had taken the medication just before bedtime with only small amounts of liquid and reported severe retrosternal pain and painful swallowing shortly thereafter. The ulcers resolved spontaneously after discontinuation of tetracycline therapy. To minimize esophageal irritation, patients should be advised to avoid taking tetracycline just before retiring and to take the medication with plenty of water.
Oral ulcers have also occurred in a patient who gargled with a tetracycline solution made by emptying the contents of a 250 mg capsule into water.[Ref]
Renal side effects generally occurred in patients with preexisting renal disease and have been the result of accumulation of tetracycline (the active ingredient contained in Tetracon) Increases in BUN commonly occur because of tetracycline's anti-anabolic effect but do not necessarily indicate renal dysfunction.
Fanconi's syndrome is characterized by renal glycosuria, phosphaturia, aminoaciduria, and acidosis with or without proteinuria and rickets. It is associated with the ingestion of outdated or degraded tetracycline. Additionally, previous formulations of tetracycline contained citric acid which may contribute to metabolic acidosis; however, current formulations of the drug do not. Patients generally require hospitalization with intravenous medication to correct the accompanying metabolic abnormalities. Most cases resolve over time after discontinuation of tetracycline without permanent sequelae. Patients should be instructed to discard any unused portions of tetracycline at the end of therapy and to never use tetracycline remaining from a previous prescription.[Ref]
Renal side effects have included increased BUN and Fanconi's syndrome. In patients with preexisting renal impairment, tetracycline may cause azotemia, hyperphosphatemia, and acidosis. Patients with dehydration are particularly vulnerable.[Ref]
Tetracycline (the active ingredient contained in Tetracon) deposits into calcium-rich developing osseous tissue thereby causing the discoloration of permanent teeth, decreased rate of enamel growth, and a decrease in linear skeletal growth rate.[Ref]
Musculoskeletal side effects have included adult tooth discoloration, enamel hypoplasia, and a decrease in linear skeletal growth rate. Tetracycline should not be administered to pregnant women or children less than 12 years of age.[Ref]
There have been several cases of benign intracranial hypertension (pseudotumor cerebri) associated with tetracycline (the active ingredient contained in Tetracon) therapy. In most cases, the patient was female and was prescribed tetracycline to treat acne. Symptoms commonly occurring in these cases consisted of severe headaches, nausea, and blurred vision. Physical examination revealed papilledema in all cases, and several had significantly increased pressure on lumbar puncture. All patients recovered over time after discontinuation of tetracycline therapy. The mechanism for development of increased intracranial pressure is unknown.[Ref]
At least two cases of tetracycline-induced hemolytic anemia have been reported. In both cases, the anemia resolved over time after discontinuation of the medication and reoccurred 1 to 2 years later following another course of tetracycline therapy. The mechanism for development of hemolytic anemia is unknown.[Ref]
Hypersensitivity side effects have included urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, exacerbation of systemic lupus erythematosus, hypersensitivity myocarditis, and serum sickness-like reactions (fever, rash, arthralgia).[Ref]
Hepatic side effects have included increased liver enzyme levels, hepatotoxicity, liver failure, and bile duct paucity with prolonged cholestasis. These may be dose-related.[Ref]
Other side effects have included superinfection due to overgrowth of resistant organisms. The long-term use of tetracyclines has been associated with microscopic brown-black discoloration of the thyroid gland; however, abnormal thyroid function has not been reported.[Ref]
Metabolic side effects have included azotemia, hyperphosphatemia, and metabolic acidosis. Increases in serum BUN levels may occur as a result of the anti-anabolic action of tetracycline (the active ingredient contained in Tetracon) and not necessarily indicate renal disease.[Ref]
These metabolic side effects have occurred more commonly in the presence of preexisting renal disease, and occur as a result of the accumulation of tetracycline.[Ref]
Frequently asked questions
More about Tetracon (tetracycline)
- Check interactions
- Latest FDA alerts (1)
- Dosage information
- During pregnancy
- Drug class: tetracyclines
- En español
Related treatment guides
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Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.