Clemastine / phenylpropanolamine Side Effects
Applies to clemastine/phenylpropanolamine: oral tablet extended release
Nearly all patients treated with clemastine experience drowsiness, which may subside in some patients with extended use. Patients should be warned against driving, as well as concomitant ingestion of alcohol and other sedative-hypnotic drugs, while taking clemastine.
Few cases of dyskinesias and tremors, often of the face, have been reported in patients whose chronic use of antihistamines extended over a period of 3 to 10 years. Some of these cases were only partially relieved by discontinuation of the drug. Haloperidol was successful in relieving symptoms.
Seizures may occur in rare cases of hypertensive crisis due to phenylpropanolamine and have been reported with normally recommended doses as well as in cases of overuse or overdose.
There have been anecdotal reports of cerebrovascular hemorrhage largely associated with an uneven pattern of cerebrovascular spasm referred to as vascular beading. Vascular beading has also been reported in the absence of hemorrhage. Intracranial hemorrhage has almost always been associated with hypertension.[Ref]
Central nervous system depression has commonly been associated with the use of clemastine. This may result in drowsiness, dizziness, and headache. Dyskinesias have rarely been reported following chronic use of antihistamines. Phenylpropanolamine can stimulate the nervous system, resulting in tremor, anxiety, insomnia, dizziness, and nervousness. Headache has also been associated with the use of phenylpropanolamine.[Ref]
Phenylpropanolamine causes vasoconstriction which usually does not result in blood pressure elevations in healthy adults given normally prescribed dosages. However, phenylpropanolamine administration may be problematic for patients with preexisting hypertension and those receiving higher dosages. In general, 75 mg of sustained-release phenylpropanolamine will not produce a significant increase in blood pressure in normotensive patients, but 150 mg of sustained-release phenylpropanolamine can.
The combination of caffeine and phenylpropanolamine is more apt to cause hypertension. Although caffeine is no longer added to phenylpropanolamine as an anorexiant, this combination is available as "look-alikes" for amphetamines. Hypertensive crisis has occurred occasionally subsequent to overusage, overdose, and ingestion of normally recommended doses. Hypertensive crisis may be accompanied by headache, blurred vision, confusion, intracranial hemorrhage, encephalopathy, or seizures.
Arrhythmias may be produced in predisposed patients. The majority of reports of arrhythmias involve overuse or overdose. Rarely, high doses of phenylpropanolamine may cause chest pain and evidence of myocardial injury.
One study reported that taking phenylpropanolamine increases the risk of hemorrhagic stroke in women. Men may also be at risk. Although the risk of hemorrhagic stoke is very low, the FDA recommends that all use of phenylpropanolamine be discontinued.[Ref]
Cardiovascular adverse effects may be associated with the use of phenylpropanolamine. Use of phenylpropanolamine can cause a significant rise in heart rate. Hypertension and arrhythmias may be problematic in susceptible patients. Cardiovascular effects of clemastine may include hypotension, tachycardia, and palpitations. Cardiovascular side effects have also included an increased risk of hemorrhagic stroke.[Ref]
Gastrointestinal reactions from clemastine include dry mouth and constipation due to its anticholinergic effects and may occur in up to one-third of patients. Gastrointestinal complaints most commonly associated with phenylpropanolamine include anorexia and gastric irritation. Nausea and vomiting have occurred in conjunction with hypertensive episodes.[Ref]
Ocular side effects of clemastine are primarily anticholinergic and may include blurred vision, diplopia, and dry eyes.[Ref]
Genitourinary side effects include dysuria, urinary hesitancy, and decreased urine flow. These side effects are thought to be due to the anticholinergic effects of clemastine. In rare cases, use of clemastine can precipitate acute urinary retention.[Ref]
A fatal case of agranulocytosis has been reported in a patient taking chlorpheniramine, pseudoephedrine, acetaminophen, dextromethorphan, phenylpropanolamine, and aspirin. However, chlorpheniramine was felt to be the cause.[Ref]
Psychiatric reactions to phenylpropanolamine occur infrequently but include acute mania, anxiety, paranoia, confusion, agitation, and hallucinations. These reactions may be more common in women.[Ref]
Psychotic reactions to phenylpropanolamine have occurred in patients receiving normally recommended doses and in cases of abuse. In a few patients, phenylpropanolamine appears to have exacerbated an underlying bipolar disorder which was previously undiagnosed.
A psychotic episode consisting of abnormal behavior was reported in a young woman following a week of therapy with Naldecon (phenylephrine, phenylpropanolamine, chlorpheniramine, and phenyltoloxamine) and amantadine. The patient had no personal or family history of psychiatric illness and no history of recreational substance use. It is uncertain whether the episode was due to the amantadine, the phenylpropanolamine or another component in the Naldecon, or an interaction between the drugs.[Ref]
Hypersensitivity reactions to phenylpropanolamine have been reported.[Ref]
Renal side effects associated with the use of phenylpropanolamine include rare cases of acute interstitial nephritis.[Ref]
1. Thach BT, Chase TN, Bosma JF "Oral facial dyskinesia associated with prolonged use of antihistaminic decongestants." N Engl J Med 293 (1975): 486-7
2. Maher LM, Peterson PL, Dela-Cruz C "Postpartum intracranial hemorrhage and phenylpropanolamine use" Neurology 37 (1987): 1686
3. Thomas JS, Heurich AE, Ralph JW, Crane R, Shepherd DA "Double-blind, controlled study of clemastine fumarate, chlorpheniramine and placebo in patients with seasonal allergic rhinitis." Ann Allergy 38 (1977): 169-74
4. Frolund L, Etholm B, Irander K, Johannessen TA, Odkvist L, Ohlander B, Weeke B "A multicentre study of loratadine, clemastine and placebo in patients with perennial allergic rhinitis." Allergy 45 (1990): 254-61
5. Dietz AJ, Jr "Amphetamine-like reactions to phenylpropanolamine." JAMA 245 (1981): 601-2
6. Edwards M, Russo L, Harwood-Nuss A "Cerebral infarction with a single oral dose of phenylpropanolamine." Am J Emerg Med 5 (1987): 163-4
7. Schaffer CB, Pauli MW "Psychotic reaction caused by proprietary oral diet agents." Am J Psychiatry 137 (1980): 1256-7
8. Kikta DG, Devereaux MW, Chandar K "Intracranial hemorrhages due to phenylpropanolamine." Stroke 16 (1985): 510-2
9. Johnson DA, Etter HS, Reeves DM "Stroke and phenylpropanolamine use" Lancet 2 (1983): 970
10. Lake CR, Tenglin R, Chernow B, Holloway HC "Psychomotor stimulant-induced mania in a genetically predisposed patient: a review of the literature and report of a case." J Clin Psychopharmacol 3 (1983): 97-100
11. Norvenius G, Widerlov E, Lonnerholm G "Phenylpropanolamine and mental disturbances" Lancet 2 (1979): 1367-8
12. Mueller SM "Neurologic complications of phenylpropanolamine use." Neurology 33 (1983): 650-2
13. "Letter: Dyskinesia associated with chronic antihistamine use." N Engl J Med 294 (1976): 113
14. Grieger TA, Clayton AH, Goyer PF "Affective disorder following use of phenylpropanolamine" Am J Psychiatry 147 (1990): 367-8
15. Cornelius JR, Soloff PH, Reynolds CF, 3d "Paranoia, homicidal behavior, and seizures associated with phenylpropanolamine." Am J Psychiatry 141 (1984): 120-1
16. Kizer KW "Intracranial hemorrhage associated with overdose of decongestant containing phenylpropanolamine" Am J Emerg Med 2 (1984): 180-1
17. Lake CR, Gallant S, Masson E, Miller P "Adverse drug effects attributed to phenylpropanolamine: a review of 142 case reports." Am J Med 89 (1990): 195-208
18. Achor MB, Extein I "Diet aids, mania, and affective illness" Am J Psychiatry 138 (1981): 392
19. Elliott CF, Whyte JC "Phenylpropanolamine and hypertension." Med J Aust 1 (1981): 715
20. Kase CS, Foster TE, Reed JE, Spatz EL, Girgis GN "Intracerebral hemorrhage and phenylpropanolamine use." Neurology 37 (1987): 399-404
21. "Product Information. Tavist-D (phenylpropanolamine-clemastine)." Sandoz Pharmaceuticals Corporation, East Hanover, NJ.
22. Schuller DE, Turkewitz D "Adverse effects of antihistamines." Postgrad Med 79 (1986): 75-86
23. Bernstein E, Diskant BM "Phenylpropanolamine: a potentially hazardous drug." Ann Emerg Med 11 (1982): 311-5
24. Schran HF, Petryk L, Chang CT, Oconnor R, Gelbert MB "The pharmacokinetics and bioavailability of clemastine and phenylpropanolamine in single-component and combination formulations." J Clin Pharmacol 36 (1996): 911-22
25. Howrie DL, Wolfson JH "Phenylpropanolamine-induced hypertensive seizures." J Pediatr 102 (1983): 143-5
26. O'Connell MB, Gross CR "The effect of multiple doses of phenylpropanolamine on the blood pressure of patients whose hypertension was controlled with beta blockers." Pharmacotherapy 11 (1991): 376-81
27. Kroenke K, Omori DM, Simmons JO, Wood DR, Meier NJ "The safety of phenylpropanolamine in patients with stable hypertension." Ann Intern Med 111 (1989): 1043-4
28. Noble R "A controlled clinical trial of the cardiovascular and psychological effects of phenylpropanolamine and caffeine." Drug Intell Clin Pharm 22 (1988): 296-9
29. Clark JE, Simon WA "Cardiac arrhythmias after phenylpropanolamine ingestion." Drug Intell Clin Pharm 17 (1983): 737-8
30. Lake CR, Zaloga G, Bray J, Rosenberg D, Chernow B "Transient hypertension after two phenylpropanolamine diet aids and the effects of caffeine: a placebo-controlled follow-up study." Am J Med 86 (1989): 427-32
31. McEwen J "Phenylpropanolamine-associated hypertension after the use of "over- the-counter" appetite-suppressant products." Med J Aust 2 (1983): 71-3
32. O'Connell MB, Gross CR "The effect of single-dose phenylpropanolamine on blood pressure in patients with hypertension controlled by beta blockers." Pharmacotherapy 10 (1990): 85-91
33. Lake CR, Zaloga G, Clymer R, Quirk RM, Chernow B "A double dose of phenylpropanolamine causes transient hypertension." Am J Med 85 (1988): 339-43
34. Pentel PR, Mikell FL, Zavoral JH "Myocardial injury after phenylpropanolamine ingestion." Br Heart J 47 (1982): 51-4
35. Chin C, Choy M "Cardiomyopathy induced by phenylpropanolamine." J Pediatr 123 (1993): 825-7
36. Horowitz JD, Lang WJ, Howes LG, Fennessy MR, Christophidis N, Rand MJ, Louis WJ "Hypertensive responses induced by phenylpropanolamine in anorectic and decongestant preparations." Lancet 1 (1980): 60-1
37. Deringer PM, Maniatis A "Chlorpheniramine-induced bone-marrow suppression." Lancet 1 (1976): 432
38. Eisner EV, LaBocki NL, Pinckney L "Chlorpheniramine-dependent thrombocytopenia." JAMA 231 (1975): 735-6
39. Hardin AS "Chlorpheniramine and agranulocytosis ." Ann Intern Med 108 (1988): 770
40. Kanoh T, Jingami H, Uchino H "Aplastic anaemia after prolonged treatment with chlorpheniramine ." Lancet 1 (1977): 546-7
41. Stroe AE, Hall J, Amin F "Psychotic episode related to phenylpropanolamine and amantadine in a healthy female." Gen Hosp Psychiatry 17 (1995): 457-8
42. Speer F, Carrasco LC, Kimura CC "Allergy to phenylpropanolamine." Ann Allergy 40 (1978): 32-4
43. Swenson RD, Golper TA, Bennett WM "Acute renal failure and rhabdomyolysis after ingestion of phenylpropanolamine-containing diet pills." JAMA 248 (1982): 1216
44. Singer DR, Simpson JG, Catto GR, Johnston AW "Drug hypersensitivity causing granulomatous interstitial nephritis." Am J Kidney Dis 11 (1988): 357-9
More about clemastine / phenylpropanolamine
Related treatment guides
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.