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Ala-Tet Side Effects

Generic name: tetracycline

Medically reviewed by Last updated on May 14, 2023.

Note: This document contains side effect information about tetracycline. Some dosage forms listed on this page may not apply to the brand name Ala-Tet.

Applies to tetracycline: oral suspension, oral tablets, oral tetracycline combinations.

Side effects include:

GI effects (anorexia, epigastric distress, nausea, vomiting, diarrhea); rash; dose-related BUN increases.

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 Ala-Tet) 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 It is associated with the ingestion of outdated or degraded tetracycline.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]


Dermatologic side effects have included exfoliative dermatitis, maculopapular and erythematous rashes, nail discoloration, onycholysis, and photosensitivity.[Ref]


Tetracycline (the active ingredient contained in Ala-Tet) 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]

Nervous system

There have been several cases of benign intracranial hypertension (pseudotumor cerebri) associated with tetracycline (the active ingredient contained in Ala-Tet) 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]

Nervous system side effects have included benign intracranial hypertension (pseudotumor cerebri) in adults and bulging fontanels in infants.[Ref]


Hematologic side effects have included hemolytic anemia, thrombocytopenia, thrombocytopenic purpura, neutropenia, and eosinophilia.[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 Ala-Tet) 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


1. Hinton NA "The effect of oral tetracycline HCl and doxycycline on the intestinal flora." Curr Ther Res Clin Exp 12 (1970): 341-52

2. Khera DC, Herschman BR, Sosa F "Tetracycline-induced esophageal ulcers." Postgrad Med J 68 (1980): 113-5

3. Channer KS, Hollanders D "Tetracycline-induced oesophageal ulceration." Br Med J 282 (1981): 1359-60

4. Nordt SP "Tetracycline-induced oral mucosal ulceration." Ann Pharmacother 30 (1996): 547-8

5. "Product Information. Tetracycline Hydrochloride (tetracycline)." IVAX Pharmaceuticals Inc (2004):

6. Shils ME "Renal disease and the metabolic effects of tetracycline." Ann Intern Med 58 (1963): 389-408

7. Jick H, Slone D, Shapiro S, et al. "Tetracycline and drug-attributed rises in blood urea nitrogen: a report from the Boston Collaborative Drug Surveillance Program." JAMA 220 (1972): 377-9

8. George CR, Evans RA "Tetracycline toxicity in renal failure." Med J Aust 06/12/71 (1971): 1271-3

9. Reddy J "Tetracycline antibiotics should be avoided in patients with renal disease." N Z Med J 94 (1981): 396

10. Sulkowski SR, Haserick JR "Simulated systemic lupus erythematosus from degraded tetracycline." JAMA 189 (1964): 152-4

11. Brown CB "Tetracycline and renal function." Br Med J 4 (1971): 428

12. Tannenberg AM "Tetracycline and rises in urea nitrogen." JAMA 221 (1972): 713

13. "Product Information. Achromycin (tetracycline)." Lederle Laboratories (2001):

14. Vassileva SG, Mateev G, Parish LC "Antimicrobial photosensitive reactions." Arch Intern Med 158 (1998): 1993-2000

15. Douglas AC "The deposition of tetracycline in human nails and teeth: a complication of long-term treatment." Br J Dis Chest 57 (1963): 44-7

16. Bevelander G "The effect of tetracycline on mineralization and growth." Adv Oral Biol 7 (1964): 205-23

17. Witkop CJ, Wolf RO "Hypoplasia and intrinsic staining of enamel following tetracycline therapy." JAMA 185 (1963): 1008-11

18. Walters BN, Gubbay SS "Tetracycline and benign intracranial hypertension: report of five cases." Br Med J 282 (1981): 19-20

19. Minutello JS, Dimayuga RG, Carter J "Pseudotumor cerebri, a rare adverse reaction to tetracycline therapy." J Periodontol 59 (1988): 848-51

20. Lee AG "Pseudotumor cerebri after treatment with tetracycline and isotretinoin for acne." Cutis 55 (1995): 165-8

21. Mazza JJ, Kryda MD "Tetracycline-induced hemolytic anemia." J Am Acad Dermatol 2 (1980): 506-8

22. Kounis GN, Kouni SA, Chiladakis JA, Kounis NG "Comment: Mesalamine-Associated Hypersensitivity Myocarditis in Ulcerative Colitis and the Kounis Syndrome (February)." Ann Pharmacother 43 (2009): 393-4

23. Frimpter GW, Timpanelli AE, Eisenmenger WJ, et al. "Reversible fanconi syndrome caused by degraded tetracycline." JAMA 184 (1963): 111-3

24. Grossman ER, Walchek A, Freedman H, Flanagan C "Tetracyclines and permanent teeth: the relation between dose and tooth color." Pediatrics 47 (1971): 567-70

Further information

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.