Interactions and contraindications
Contraceptive effectiveness of the patch or any other hormonal contraceptive may be reduced significantly if administered alongside various antibiotics, antifungals, anticonvulsants, or other drugs that increase metabolism of contraceptive steroids.However, despite the interactions with many other antibiotics, a clinical pharmacokinetic drug interaction study showed that oral administration of tetracycline HCl 500 mg for three days prior to and seven days during use of Ortho Evra "did not reduce effectiveness of Ortho Evra." This is a significant factor in the common decision to administer tetracycline-derived antibiotics following an abortion (preventatively to fight potential infection) when synthetic hormone contraceptives are to be used afterwards.Drugs containing St. Johns wort are also known to affect the effectiveness of hormonal contraceptives.It has also been found that the patch is less effective in women who weigh more than 198 pounds (90 kg). The contraceptive patch and other combination hormonal contraceptives are contraindicated in women older than 35 years who smoke cigarettes.The contraceptive patch is contraindicated for use in women with a BMI ≥ 30 kg/m2. Thromboembolism
All combined hormonal birth control products have a very small increased risk of serious or fatal thromboembolic events. There is ongoing research into the thromboembolic risks of Ortho Evra as compared to combined oral contraceptive pills. A recent study found that users of the contraceptive patch may have a twofold increased risk for non-fatal venous thromboembolic events compared with women who took a norgestimate-containing oral contraceptive with 35 µg of estrogen.
In contrast, however, mouth breathing "pulls all pollution and germs directly into the lungs; dry cold air in the lungs makes the secretions thick, slows the cleaning cilia, and slows down the passage of oxygen into the bloodstream." As a result, chronic mouth breathing may lead to illness. In about 85% of cases, it is an adaptation to nasal congestion,: 281  and frequently occurs during sleep. More specialized causes include: antrochoanal polyps;: 350  a short upper lip which prevents the lips from meeting at rest (lip incompetence);: 281  and pregnancy rhinitis which tends to occur in the third trimester of pregnancy. : 435

Potential effects
Conditions associated with mouth breathing include cheilitis glandularis,: 490  Down syndrome,: 365  anterior open bite,: 225  tongue thrusting habit,: 225  cerebral palsy,: 422  ADHD, sleep apnea, and snoring. In addition, gingivitis,: 85  gingival enlargement,: 85  and increased levels of dental plaque: 108  are common in persons who chronically breathe through their mouths. The usual effect on the gums is sharply confined to the anterior maxillary region, especially the incisors (the upper teeth at the front). The appearance is erythematous (red), edematous (swollen) and shiny. This region receives the greatest exposure to airflow during mouth breathing, and it is thought that the inflammation and irritation is related to surface dehydration, but in animal experimentation, repeated air drying of the gums did not create such an appearance. : 85 Breathing through your mouth decreases saliva flow. Saliva has minerals to help neutralize bacteria, clean off the teeth, and rehydrate the tissues.