Editor’s note: This is Part 2 of an update of an article on the use of Meclizine for vertigo that first appeared in print in Advance for Audiologists in 2000.
The Physicians Desk Reference lists adverse reactions for meclizine, noting that “Drowsiness, dry mouth and, on rare occasions, blurred vision have been reported.” But what about functional impact? Could meclizine potentially make your symptoms worse?
Negative Effects of Meclizine (Antivert)
In a study conducted by Kennedy et al., psychomotor tests and questionnaires were administered to a group of healthy young adults who received therapeutic doses of various medications commonly used for motion sickness, including meclizine and hyoscine (scopolomine).
The results of the study revealed that while there were no major declines observed in several psychomotor tests, meclizine had a significant negative impact on balance tests that required participants to stand on a balance beam. It is important to consider a potential caveat associated with this study, namely that the tests were conducted within one to two hours after the participants ingested the medications.
Subsequent research, however, indicated that meclizine’s peak effect on the central nervous system occurs approximately 9 hours after dosing, suggesting that the detrimental effect on balance may be more pronounced during this time frame.
This insight emphasizes the need for further investigation into the temporal dynamics of meclizine’s effects on balance and highlights the importance of timing when assessing its functional impact.
Future studies that consider the delayed peak effect of meclizine could provide a more comprehensive understanding of its potential implications for individuals relying on balance and motor coordination in various activities.
Is “Buzzed” Balance the Same as “Drunk” Balance ?
Manning et al. explored the central nervous system effects of meclizine and dimenhydrate (Dramamine). Their results “demonstrate that both dimenhydrate and meclizine, in recommended doses, produce drowsiness and impaired mental performance greater than placebo.” These authors attempt to “interpret the meaning of the observed decrement in test scores” by comparing their results to the effects of ethanol (alcohol):
“Ethanol serves as a unique drug to reference degree of impairment because there are epidemiologic data that relate to blood alcohol concentrations with a known risk (.07 percent) for being involved in a traffic accident.”
Comparison of the data demonstrates that the effect of dimenhydrate and meclizine on mental reaction time is equal to that observed while blood alcohol levels were .04 percent to .06 percent.
Effects on Postural Control
Two recent studies demonstrate the efficacy of vestibular therapy vs. medication in improving postural control in patients with vestibular deficiency. Horak et al. compared “relative effectiveness of vestibular rehabilitation, general conditioning exercises and vestibular suppressant medication” on subjective dizziness and postural control. The medication group was treated with Valium or Meclizine, both centrally sedating medications. Over a six-week treatment period, all groups reported a reduction in symptoms, but only the vestibular rehabilitation group showed significant objective improvement in scores obtained from posturography and standing balance tests.
The use of centrally sedating medication may impede the benefits of vestibular rehabilitation therapy. Shepard et al. reported that patients taking vestibular suppressants, antidepressants, tranquilizers and anticonvulsants ultimately achieved the same level of compensation as patients not taking similar medications, but the length of therapy was significantly longer.
Antivert is helpful for vertigo associated with sudden acute vestibular asymmetry due to Menieres disease or vestibular neuronitis, but should be withdrawn once the acute symptoms have diminished. It is not recommended for complaints of unsteadiness, loss of balance, and disequilibrium, whether of vestibular origin or not. Vertigo related to BPPV is better treated through canalith repositioning techniques.
The Bottom Line?
Long-term use of Antivert is inappropriate, and the drug may be overprescribed in the primary care setting.
Alan Desmond, AuD, is the director of the Balance Disorders Program at Wake Forest Baptist Health Center, and holds an adjunct assistant professor faculty position at the Wake Forest School of Medicine. He has written several books and book chapters on balance disorders and vestibular function. He is the co-author of the Clinical Practice Guideline for Benign Paroxysmal Positional Vertigo (BPPV). In 2015, he was the recipient of the President’s Award from the American Academy of Audiology.
**this piece has been updated for clarity. It originally published on October 8, 2013
