Table 3 Adverse events experienced by both groups at baseline and at week 24. Scale: 4 = severe, 3 = Moderate, 2 = Mild, 1 = slight, 0 = absent; ^aFisher’s exact test

Dry Mouth

Dual user

Sole EC user

82 (55.4)

30 (42.9)

1.229

0.900

0.062

21 (16.5)

09 (14.5)

.2205

.2097

0.904

Sore throat

Dual user

Sole EC user

32 (21.6)

9 (12.9)

.3986

.2714

0.262

13 (10.2)

8 (12.9)

.1102

.1290

0.720

Cough

Dual user

Sole EC user

34 (23)

8 (11.4)

0.5473

0.1571

< 0.001

31 (24.4)

7 (11.3)

.3858

.1452

0.009

Anxiety

Dual user

Sole EC user

0 (0)

1 (1.4)

.0000

.0286

0.321

–

–

–

Stomach disturbances

Dual user

Sole EC user

2 (1.4)

0 (0)

.0270

.0000

0.158

–

–

–

Nausea

Dual user

Sole EC user

–

–

–

6 (4.7)

2 (3.2)

.0551

.0323

0.535

Vomiting

Dual user

Sole EC user

0 (0)

5 (7.1)

0.000

0.1571

0.033

3 (2.4)

2 (3.2)

.0394

.0484

0.830

Headache

Dual user

Sole EC user

14 (9.5)

6 (9.2)

.1486

.1286

0.771

5 (3.9)

5 (8.1)

.0551

.0968

0.388

Breathing

Problem

Dual user

Sole EC user

27 (18.8)

2 (2.8)

.3243

0429

< 0.001

24 (18.9)

4 (6.5)

.2598

.0806

0.008

Other (fever, gums bleeding

Dual user

Sole EC user

0 (0)

3 (4.3)^a

.0000

.0571

0.103

1 (0.8)

2 (3.2)^b

.1102

.0806

0.775