Sudden hearing loss, sometimes with tinnitus, has been reported after Viagra, Cialis and related drugs; it is rare, a causal link is unproven, and the Viagra and Cialis labels say to stop and seek prompt care if it happens.
These drugs are the phosphodiesterase type 5 (PDE5) inhibitors: sildenafil (sold as Viagra, and as Revatio for pulmonary arterial hypertension), tadalafil (Cialis, and Adcirca for pulmonary arterial hypertension), vardenafil (Levitra) and avanafil. They are used mainly for erectile dysfunction, and also for pulmonary hypertension and benign prostatic hyperplasia.
If your hearing drops after taking one
- Treat it as urgent. The US National Institute on Deafness and Other Communication Disorders (NIDCD) says to consider sudden deafness a medical emergency and see a doctor immediately. Sudden hearing loss explains why the first days matter and what the assessment involves.
- Stop the drug if you take it for erectile dysfunction or an enlarged prostate. The current Viagra and Cialis labels tell prescribers to advise patients to stop taking PDE5 inhibitors and seek prompt medical attention in the event of a sudden decrease or loss of hearing.
- Do not stop it on your own if you take it for pulmonary hypertension. In 2007 the FDA said people taking Revatio should keep taking it and contact their provider, because it treats a potentially life-threatening condition. Today the Revatio and Adcirca labels advise prompt medical attention, and their leaflets say not to stop without talking to your healthcare provider.
- Say which drug you took, the dose and when. A 2009 case review concluded that ear specialists should ask about PDE5 inhibitor use in anyone with sudden hearing loss, so volunteer it.
- Expect a hearing test, which is what tells an inner-ear loss from a blocked ear. For other ear symptoms, the when to seek care tool sorts them by urgency.
NIDCD notes that people often notice sudden hearing loss on waking or when using the phone, sometimes just after a loud pop, and that it frequently affects only one ear.
What the FDA did in 2007, and what the labels say now
On 18 October 2007 the FDA announced labelling changes for Cialis, Levitra and Viagra to display the potential risk of sudden hearing loss more prominently, and said it planned to require the same for Revatio.
It started with one case. A report in the April 2007 issue of The Journal of Laryngology & Otology described a 44-year-old man with profound hearing loss in both ears, which did not recover, after taking sildenafil 50 mg a day for 15 days. The FDA then searched its adverse event reporting system and found 29 postmarketing reports of sudden hearing loss, with or without ringing in the ears, vertigo or dizziness. Most involved one ear. In about a third the loss was temporary; in the rest it was ongoing when reported, or the outcome was not described.
The agency said that no causal relationship had been demonstrated, and that the strong relationship between use of the drugs and hearing loss in those cases warranted a label change.
Today the Viagra and Cialis prescribing information states that these events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association with PDE5 inhibitors, and that it is not possible to determine whether they are related directly to the drugs, to the patient's own risk factors for hearing loss, or to other factors.
How often it happens
The best estimate comes from a 2018 cohort study in Pharmacoepidemiology and Drug Safety. It used US insurance claims to follow 377,722 men who started a PDE5 inhibitor and 1,957,233 who did not, between 1998 and 2007, and counted sudden hearing loss only when the diagnosis came with at least two billing codes for hearing tests within 30 days.
- Sudden hearing loss occurred at 4.35 per 10,000 person-years during current use, against 2.38 in non-users.
- After adjustment for age and a propensity score, the hazard ratio for current use was 1.25 (95% CI 1.01–1.55).
- The risk difference was 1.97 per 10,000 person-years: about 2 more cases among users than non-users for every 10,000 person-years of follow-up.
The authors describe a small but significantly increased risk. Use was estimated from pharmacy records on the assumption of one dose a week, and the results held when that assumption was varied. The risk was higher still in the period the authors classed as recent use (hazard ratio 1.60).
Why a cause has not been proven
The difficulty with every comparison is that men prescribed these drugs are not a random sample of men.
Erectile dysfunction and sudden hearing loss appear to go together whether or not a drug is involved. A 2012 case-control study from Taiwan compared 4,504 men with erectile dysfunction against 22,520 controls. A previous diagnosis of sudden hearing loss was found in 0.49% of the men with erectile dysfunction and 0.08% of controls, an adjusted odds ratio of 6.06 after accounting for hypertension, diabetes, high cholesterol, coronary heart disease, obesity and alcohol problems. A 2013 Taiwanese cohort looked the other way: 23,212 men with sudden hearing loss were more likely than matched controls to be diagnosed with erectile dysfunction later (hazard ratio 1.94). Both groups of authors read this as a sign of a shared vascular mechanism.
A small 2025 study points the same way: 30 PDE5 inhibitor users already had poorer extended high-frequency hearing than 30 healthy controls before taking the medication, with further deterioration afterwards.
So the men who take these drugs may start at higher risk. The 2018 cohort adjusted for what claims data can capture, and no observational study can adjust for everything.
The other kinds of evidence do not settle it either:
- A survey. A 2010 cross-sectional study of 11,525 US men aged 40 and over found that those reporting hearing impairment were more likely to report PDE5 inhibitor use (odds ratio 2.23), an association limited to sildenafil. Its author notes that the design gives only limited insight.
- Reporting databases. An analysis of FDA adverse event reports from 2004 to 2022 found 2,608 hearing impairment cases among 191,398 reports for PDE5 inhibitors, with reporting odds ratios from 2.69 for vardenafil to 4.35 for avanafil; sildenafil, at 3.03, had the most cases. Another found reports for every drug except avanafil rising from 2008, the year after the labelling change. As the Cialis label notes, voluntary reports come from a population of uncertain size, so their frequency cannot always be reliably estimated.
- Hearing tests around a dose. In 18 men tested before and 1, 5 and 72 hours after a dose, four showed a temporary one-sided threshold change that met ototoxicity criteria, with no permanent effect. In 25 people starting tadalafil, hearing did not change significantly over 30 days, though 3 taking 20 mg daily for pulmonary hypertension showed higher thresholds at high frequencies.
- Clinical trials. A review of 67 placebo-controlled sildenafil trials run by the manufacturer, with more than 14,000 men, and of its postmarketing database found no new safety risk relating to hearing loss. Even trials this large are poorly placed to detect an event the cohort study measured at a few cases per 10,000 person-years.
A 2019 systematic review in Otology & Neurotology found that every prospective study had failed to show a significant association, that the retrospective studies were mixed, and that laboratory work points both ways, towards harm to the ear and towards protection. It called the literature inconclusive. A 2026 systematic review of the case reports called for larger studies with control groups before a causal link can be established. Reading a tinnitus study covers why a result with no comparison group cannot separate a cause from what would have happened anyway.
What the reported cases look like
- Timing. A 2009 review of 25 cases, drawing on FDA postmarketing data, found that 15 (reported as 88%) began within 24 hours of a dose. A 2011 review of 47 cases put onset within 24 hours in 18, reported as 66.7%.
- One ear. The loss was one-sided in 96% of the 2009 cases and 88% of the 2011 cases, whose average age was 56.6.
- Other symptoms. Vertigo accompanied the hearing loss in 32% of the 2009 cases. In the 2026 review's 54 patients, 4 (7%) had tinnitus and 3 (5%) vertigo.
- Recovery. In the 2009 series, hearing recovered completely in 5 patients (20%) and partly in 3 (12%). The 2026 review had long-term outcomes for only 7 patients: 4 did not improve, 2 recovered fully and 1 partly.
These numbers are too small and selective to predict any one person's outcome, but permanent loss is among them.
What might explain it
Nobody knows. The 2009 authors proposed a prolonged effect of cGMP, a signalling molecule inside cells, within the cochlea, while noting there was no direct evidence for any mechanism.
Single case reports point elsewhere. One man developed low-frequency hearing loss with fullness and tinnitus a day after taking tadalafil; MRI showed a swollen cochlear duct (cochlear hydrops), and he improved on acetazolamide. Another, a man in his thirties whose hearing change after sildenafil resolved over three days, had test results the authors thought most likely reflected a bleed inside the cochlea, possibly from physical exertion rather than the drug.
That second report matters for reading the timing: a drug taken for sex and sex itself happen close together, and a case report cannot separate the two.
Viagra and tinnitus on its own
Tinnitus appears twice on the Viagra and Cialis labels: in the list of less common events, each reported by under 2% of people in controlled trials, where the causal relationship is called uncertain; and in the hearing loss warning, as something that may accompany a sudden drop in hearing.
Tinnitus was recorded in only a minority of published cases: 2 of 9 patients in the 2019 review's case reports, and 4 of 54 (7%) in the 2026 review. That may partly reflect what case reports chose to record; the labels and the FDA's 29 reports both mention ringing alongside the hearing loss.
That gives a practical distinction. Ringing that arrives with muffled or reduced hearing, often in one ear, is the labelled warning sign and belongs in the urgent section above. New tinnitus with hearing that seems normal is not what the warning describes, though it is still worth raising with the prescriber and having your hearing checked, the general advice for tinnitus that starts after a new medicine in ototoxic medications.
Could these drugs help tinnitus instead?
Unpublished patient reports that vardenafil eased tinnitus led to a test. A small 2009 randomised, double-blind pilot trial gave 42 people with chronic tinnitus vardenafil 10 mg twice a day or placebo for 12 weeks. Vardenafil was no better than placebo on the tinnitus questionnaire, quality of life, hearing tests or blood markers of oxidative stress. The authors concluded that, given the unclear risk of hearing impairment, PDE5 inhibitors are not appropriate for chronic tinnitus, which fits the wider record of drugs tried for tinnitus.
If you take one of these drugs
- Weigh the warning with the prescriber. A 2018 safety review in Sexual Medicine Reviews, whose literature search ended in 2016, before the cohort study, concluded that PDE5 inhibitors are safe and first-line treatment for most erectile dysfunction, and that whether they cause sensorineural hearing loss remains uncertain.
- Know the one symptom that needs prompt care: a sudden drop in hearing, with or without ringing, fullness or dizziness.
- Mention past hearing problems. The Revatio and Adcirca patient leaflets ask people to tell their provider if they have ever had ringing in the ears, dizziness or hearing loss; the Viagra and Cialis leaflets do not. The studies above do not say what an earlier episode of sudden hearing loss means for later use, so that is a decision to make with the prescriber.