Substance use: cigarette smoking Flashcards
How common is smoking? Why is it a problem?
- 10million smokers in UK
- Biggest cause of premature death and preventable disease in UK
- Killls 100,000/year in UK
- Half of smokers die of a smoking related condition
What are the health concers from smoking?
- Premature death - mainly from lung cancer, COPD, CHD
- Cancers of the upper respiratory tract, oesophagus, bladder, kidney, stomach, pancreas, myeloid leukaemia
- Pneumonia
- CVA, aortic aneurysm, HF caused by CHD
- Peptic ulcers
- Peripheral arterial disease (including Buerger’s disease)
- Macular degeneration
- Impotence, infertility
- Skin wrinkling, osteoporosis
- Increased severity of asthma, URTIs, diabetic retinopathy
What are the effects of smoking on the foetus and on children?
Passive smoking on children:
- increased risk of sudden infant death syndrome,
- asthma,
- otitis media
- more chest infections in first year of life
Fetal exposure to maternal smoking:
- increases risk of miscarriage,
- premature birth,
- low birth weight and stillbirth.
- Smoking in pregnancy may also affect a child’s physical growth and academic attainment may be reduced
What are the benefits of smoking cessation?
Quitting at any age provides immediate and long-term health benefits *
Cost-effective way of reducing ill health
For men who smoked one cigarette per day had 46% of the excess risk of heart disease and 41% of the excess risk of stroke associated with smoking 20 cigarettes per day (much higher than the expected 5%). For women, those who smoked one cigarette per day had 31% of the excess risk of heart disease and 34% of the excess risk of stroke associated with smoking 20 cigarettes per day.
How does NICE recommend planning smoking cessation treatment with the patient?
- NRT/varenicline/buproprion should be offered to a patient who is abstaining from smoking*
- A target stop date should be set for smoking
- The treatment should be given to last only 2 weeks NRT and 3-4weeks of varenicline/bupropion after the target stop date
- If the attempt to quit is unsuccessful, do not offer repeat prescription until 6 months later unless special circumstances hampered the attempt.
*A reminder about the health benefits of smoking cessation and brief advice should be given at every opportunity in primary and secondary care. If appropriate refer to the NHS Stop Smoking service.
List the different types of NRT available and the doses of nicotine in each.
- Patches - 16 or 24hr patches. First give a high strength patch for 6-8 weeks then medium for 2 weeks and low for 2 weeks.
- Gum - 2mg and 4mg. Max 60mg daily.
- Nasal spray - 500mcg/spray. Twice an hour for 16hrs daily.
- Mouth spray - 2 sprays when urge to smoke appears
- Inhalation cartridge -15mg inhaled when urge appears
- Lozenges - one every 1-2hrs
- Sublingual tablets - 2mg each, one each hour
- Higher-dose gum and patches are more effective in those smoking more than 10 cigarettes a day.
- NRT can control the weight gain commonly associated with cessation.
At what age can you receive NRT?
NRT is licensed for use in children from the age of 12.
What are the side effects of NRT?
- Nausea
- Dizziness
- Flu-like symptoms
- Palpitations
- Dyspepsia
- Hiccups
- Insomnia
- Vivid dreams
- Myalgia
NRT should be continued for 8 weeks. 5% of those who quit continue to use NR daily (small risk of dependance).
When is NRT contraindicated?
- Severe cardiovascular disease (severe arrhythmias, post infarction period)
- Recent cerebrovascular accident (including TIA)
Caution in:
- CVD
- PVD
- hyperthyroidism
- DM
- Phaeochromocytoma
- Renal impairment
- Hepatic impairment
- Gastritis
- Peptic ulcers
What is Varenicline/Champix? What is the mechanism of action?
Alpha4-beta2 nicotinic AChR partial agonist
MOA:
- Blocks AND stimulates the receptor which is located in the nucleus accumbens area (“pleasure centre”).
- The stimulatory effect produces a weak nicotine-like effect which reduces the craving for nicotine itself,
- whilst the blocking effect inhibits the pleasurable effect derived from smoking.
What doses of Varenicline are prescribed?
Prescribe 1-2 weeks before target stop date, alongside behavioural support
- 500mcg OD for 3 days
- then 500mcg BD for 4 days
- then 1mg BD for 11 weeks (or reduce to 500mcg)
- can be given for a further 12 weeks at that dose if patients require
When is Varenicline contraindicated?
- Pregnancy
- Age under 18yrs
Cautions:
- Hx of psychiatric illness - suicidal thoughts may be observed; ask to seek help if these appear
- Severe renal impairment
- Breast feeding
- Irritability, urge to smoke, depression/insomnia on stopping the drug
What are the side effects of Varenicline?
Nausea (30%)
Insomnia , abnormal dreams, headaches, flatulence
What is Bupropion/Zyban? What is its mechanism of action?
Initially developed as an antidepressant. It is an atypical antidepressant similar to diethylpropion (an appetite stimulant) .
MOA:
- inhibits reuptake of dopamine, serotonin and NA in the CNS
- It is a non-competitive nicotine receptor antagonist .
When is Bupropion contraindicated?
- Seizures
- Eating disorders
- CNS tumours
- Acute alcohol/benzodiazepine withdrawal
- Pregnancy/breast feeding
- Bipolar illness
- Age under 18yrs
Cautions:
- Renal/hepatic impairment
- Seizures
- HTN
- May impair skilled tasks e.g. driving
