EVIDENCE-BASED ANSWER
YES, BUT THE EFFECT VARIES BY CONDITION. Direct-to-consumer advertising (DTCA) is associated with both higher fidelity to minimum treatment recommendations for depression and higher prescribing levels of antidepressants for depression and adjustment disorder (strength of recommendation [SOR]: B, small randomized controlled trial [RCT]). DTCA is also associated with higher prescribing rates for osteoarthritis, allergies, and hyperlipidemia (SOR: C, time-series analyses).
No changes in prescribing rates have been noted for hypertension and benign prostatic hyperplasia (SOR: C, time-series analyses).
Physicians often accommodate requests for DTCA medications (SOR: C, 4 surveys). In some cases, they wouldn’t have considered such prescriptions for other similar patients (SOR: C, 3 surveys).
Evidence summary
An RCT demonstrated increased prescribing rates when unannounced, standardized patients who imitated symptoms of either major depression or adjustment disorder requested a prescription. In 298 visits, 152 family physicians and internists prescribed antidepressants at significantly different rates when patients mimicking major depression requested brand-specific (53%), general (76%), or no medication (31%) (P<.001). Corresponding rates for adjustment disorder were 55%, 39%, and 10% (P<.001). The study found no difference in prescribing rates between family physicians and internists or between male and female physicians.
For patients presenting with depression, physician fidelity to minimum recommended treatment (defined as any combination of antidepressants, mental health referral, and 2-week follow-up) was 90% for patients making a brand-specific request, 98% for those making a general request, and 56% for those making no request (P<.001).1
Patients who ask for DTCA meds are more likely to get a prescription
A cross-sectional survey compared prescribing decisions by 38 US and 40 Canadian physicians for 1431 patients. Most physicians fulfilled requests for DTCA medications (US 78%, Canadian, 72%). Patients who requested a DTCA medication were far more likely to receive a new prescription (DTCA or other) than patients who didn’t (odds ratio [OR]=16.9; 95% confidence interval [CI], 7.5-38.2). Although DTCA is illegal in Canada, market contamination seems likely, because the study was done in Vancouver, British Columbia.
US patients made more requests for DTCA medications (OR=2.2; 95% CI, 1.2-4.1) than Canadian patients. When patients made DTCA-related requests, physicians considered 50% of new prescriptions to be only “possible” or “unlikely” choices for other similar patients, compared with only 12.4% when patients didn’t make such requests (P<.001).2
DTCA drugs often trump other options
A national telephone survey of 3000 adults found that 35% of respondents were prompted by DTCA to discuss the medication or related health concern at a doctor visit. Of these, 72.9% reported receiving a new prescription, and 43% of them were for the advertised drug.3
Another survey of 643 physicians showed that 39% of visits influenced by DTCA resulted in new prescriptions for the advertised drug. Physician stated they prescribed the DTCA medication because they wanted to:
- prescribe the most effective drug (46%),
- accommodate the request despite other equally effective options (48%), or
- accommodate the request despite more effective options (5.5%).
Medications other than the advertised drug were prescribed during 22% of DTCA influenced visits.4
DTCA and prescriptions: Mixed results
A time-series analysis examined the relationship between advertising expenditures for several types of drugs and prescriptions written from 1992 to 1997.5
Advertising for antilipemic drugs was positively associated with prescriptions for both antilipemics in general (41 prescriptions for every $1000 of advertising; P=.003) and Zocor in particular (23/$1000; P<.001). Advertising for antihistamines in general and Claritin in particular were both positively associated with prescriptions for Claritin (general advertising: 24/$1000; P=.004; Claritin-specific advertising: 45/$1000; P=.005).