Oral Adverse Effects of Drugs Part 2

Continued from Part 1


Tobacco and alcohol use are important risk factors for leukoplakia and oral cancer.

Drug-related pemphigoid and other bullous disorders

Drug-induced pemphigoid may be due to drugs acting as haptens or drug-induced immunological dysfunction.

Drugs most commonly implicated

  • Diclofenac
  • Penicillamine

Drug-related pemphigus

Pemphigus vulgaris may occasionally be associated with active thiol groups in the molecule, such as penicillamine and captopril, or by rifampicin or diclofenac.

Drugs most commonly implicated

  • Diclofenac
  • Penicillamine
  • Rifampicin

Drug-related erythema multiforme (and Stevens-Johnson syndrome)

A wide range of drugs may give rise to erythema multiforme, and it may be impossible to clinically distinguish drug-induced erythema multiforme from disease due to other causes.

Drugs most commonly implicated

  • Allopurinol
  • Barbiturates
  • Carbamazepine
  • NSAIDs
  • Penicillin
  • Phenytoin
  • Sulfonamides

Drug-related lupus-like disorders

Systemic lupus erythematosus (SLE) may be induced by a wide variety of different drugs.

Drugs most commonly implicated

  • Hydralazine
  • Isoniazid
  • Procainamide

Drug-related cheilitis

Cheilitis (Inflammation and cracking of the skin of the lips) is commonly caused by contact reactions to cosmetics or foods, but drugs may be implicated.

Drugs most commonly implicated

  • Etretinate
  • Indinavir
  • Isotretinoin
  • Protease inhibitors
  • Vitamin A

Drug-related superficial transient mucosal discoloration

Superficial transient discoloration of the dorsum of the tongue and other soft tissues and teeth may be of various colors, typically yellowish or brown and may be caused by some foods and beverages (coffee and tea) and some drugs (iron salts, bismuth, chlorhexidine or antibiotics), especially if these also induce dry mouth.

Drugs most commonly implicated

  • Amalgam
  • Drug causing dry mouthwashes
  • Smoking / tobacco

Drug-related intrinsic pigmentation

Localized areas of pigmentation of the mucosa may be due to amalgam, while gum pigmentation may be secondary to the gold or metal alloys of crown. Heavy metal salts, used in the past, caused pigmentation, particularly of the gum margin. Blue, blue-gray or brown mucosal pigmentation can be an adverse affect of antimalarials, phenothiazines and phenytoin or amidarone. Minocycline frequently causes widespread brown pigmentation of the gums and mucosa.

Drugs most commonly implicated

  • Antimalarials
  • Ciprofloxacin
  • Fluoride
  • Heavy metal salts
  • Minocycline
  • Tetracyclines

Drug-related gum enlargement

Gum enlargement is a well-recognized oral side effect of treatment with phenytoin, cyclosporin and the calcium-channel blockers.

Drugs most commonly implicated

  • Amlodipine
  • Basiliximab
  • Cyclosporin
  • Diltiazem
  • Felodipine
  • Lacidipine
  • Nifedipine
  • Oral contraceptives
  • Phenytoin
  • Verapamil

Drug-related lip and mucosal swelling

Drug-induced mucosal swelling predominantly affects the lips and floor of the mouth. It is typically due to type I hypersensitivity reactions. Many drugs, particularly penicillins, angiotensin-convertign enzyme inhibitors and aspirin can cause angioedema.

Drugs most commonly implicated

  • Angiotensin converting enzyme inhibitors

Drug-related trigeminal neuropathies

Facial or oral paresthesia (partial loss of sensitivity), hypoesthesia (decreased sensitivity) or anesthesia (complete loss of sensitivity) can be due to interferon alpha, acetazolamide, articaine, labetolol, sulthiame, vincristine and occasionally to some other agents such as hepatitis B vaccination and some of the protease inhibitors.

Drugs most commonly implicated

  • Acetazolamide
  • Articaine
  • Labetolol
  • Protease inhibitors
  • Vincristine

Drug-related involuntary facial movements

Several different drug-induced movements can affect the mouth and face, particularly tardive dyskinesia (late occurring abnormal muscle movement secondary to antipsychotics) and dystonias (abnormal muscle tone for example with metoclopramide). Although these disorders principally affect the face, there can be abnormal movements of the tongue, for example dystonia secondary to carbamazepine therapy.

Drugs most commonly implicated

  • L-dopa
  • Metoclopramide
  • Phenothiazines

Drug-related bad breath

Oral malodor may be related to treatment with isosorbide dinitrate, dimethyl sulphoxide or disulfram, although drugs causing dry mouth can indirectly cause or aggravate this problem.

Drugs most commonly implicated

  • Drugs causing dry mouth

Drug-related orofacial pain and oral dysesthesia

Captopril and lisinopril may very rarely cause a scalded-type sensation of the mouth.

Drugs most commonly implicated

  • Angiotensin converting enzyme inhibitors
  • Vinca alkaloids

Drug-related tooth discoloration

Certain drugs can discolor teeth internally (intrinsic) or supericially (extrinsic).

Drugs most commonly implicated

  • Clorhexidine
  • Fluorides
  • Iron
  • Tetracyclines

Drugs that may lead to tooth structure damage

Sugar-containing oral (liquid) medication and drugs that result in decreased salivary secretion can cause tooth decay. Drugs with a low pH (for example aspirin and antiasthmatic drugs) and those that cause gastric reflux (for example anticholinergics and theophylline) can lead to erosion of teeth. Tooth wear can occur with drugs inducing bruxism or teeth grinding (such as dopamine agonists, dopamine antagonists, tricyclic depressants, alcohol and cocaine).

Hydrogen peroxide and sodium perborate used for internal tooth bleaching can cause root resorption near the crown. Abnormal dental development can occur with usage of cytotoxic drugs for treatment of childhood cancers. Fluorosis is a common side effect of fluoride overdose.

Drug-related osteonecrosis

Bisphosphonates related osteonecrosis of the jaws is a condition where jaw bone is exposed in the mouth in individuals taking these drugs. The condition appears to be progressive and there is no established effective treatment although several are being investigated.