BNF - Chapter 4 - Nervous System - (Part 2) Flashcards
Which drugs may be classed as adjuvant analgesics for chronic pain?
Drugs such as
- Antidepressants
(either amitriptyline, citalopram, duloxetine, fluoxetine, paroxetine, or sertraline to manage chronic primary pain, may be considered)
Which pain relief medications are better for musculoskeletal conditions?
- Non-opioid drugs
paracetamol and aspirin (and other NSAIDs)
What are opioid analgesics more suitable for?
Particularly of visceral origin
What is sickle cell disease?
Sickle cell disease is a group of disorders that affects hemoglobin , the molecule in red blood cells that delivers oxygen to cells throughout the body. People with this disease have atypical hemoglobin molecules called hemoglobin S, which can distort red blood cells into a sickle , or crescent, shape.
How is the pain in mild sickle-cell crisis managed?
- With paracetamol, a NSAID, codeine phosphate or dihydrocodeine tartate
How may the pain need to be managed in severe sickle-cell crisis?
- Morphine or diamorphine
Concomitant use of NSAID may potentiate analgesia and allow lower doses of the opioid to be used.
Why is pethidine hydrochloride avoided if possible in sickle-cell disease?
Because accumulation of a neurotoxic metabolite can precipitate seizures; the relatively short half-life of pethidine hydrochloride necessitates frequent injections
What is most dental pain relieved with?
- NSAIDs that are used for dental pain which include - ibuprofen, diclofenac sodium and aspirin.
Paracetamol has analgesic and antipyretic effects but no anti-inflammatory effect
Are opioid analgesics helpful in dental pain?
Opioid analgesics are relatively ineffective in dental pain and their side effects can be unpleasant.
How long is postoperative analgesia with ibuprofen or aspirin usually continued for?
For about 24 to 72 hours.
What is dysmennorhoea?
It is characterised by severe and frequent menstrual cramps and pain during period.
What can be used to prevent pain of dysmenorrhoea?
- Use of oral contraceptives
- paracetamol or NSAID
Antispasmodics (such as alverine citrate) have been advocated for dysmenorrhoea but the antispasmodic action does not generally provide significant relief.
Gastric irritation may be a problem with aspirin, how may this be minimised?
- it is minimised by taking the dose after food.
Enteric coated preparations are available, but have a slow onset of action and are therefore unsuitable for single-dose analgesic use (though their prolonged action may be useful for night pain)
Which drug interaction with aspiring is a special hazard?
Aspirin + Warfarin
Which drug has a role in the relief of persistent pain unresponsive to other non-opioid analgesics?
Nefopam hydrochloride
It causes little or no respiratory depression, but sympathomimetic and antimuscarinic side effects may be troublesome
Which non-opioid analgesic is licensed to be adminstered via intrathecal infusion for the treatment of chronic severe pain?
Ziconotide (Prialt )
What role does caffeine play in compound analgesics?
Caffeine is a weak stimulant that is often included in small doses in analgesic preparations.
It is claimed that the addition of caffeine may enhance the analgesic effect, but he altering effect, mild habit-forming effect and possible provocation of headache may not always be desirable.
Moreover, in excessive dosage or on withdrawal caffeine may itself induce headache.
Which opioid has both opioid agonist and antagonist properties?
Buprenorphine
does morphone or buprenorphine have a longer duration of action?
Buprenorphine has a much longer duration of action than morphine and sublingually is an effective analgesic for 6 to 8 hours.
Are the effects of buprenorphine fully reversed by naloxone?
Unlike most opioid analgesics, the effects of buprenorphine are only partially reversed by naloxone
Which opioid is known as heroin?
Diamorphine hydrochloride which is a powerful opioid analgesic.
Which causes more nausea and hypotension between morphine and diamorphine?
Diamorphine may cause less nausea and hypotension
Which is more soluble, morphine or diamorphine and what is the advantage of this?
In palliative care the greater solubility of diamorphine hydrochloride allows effective doses to be injected in smaller volumes and this is important in the emaciated patient.
Which three opioids are used by injection for intra-operative analgesia?
- Alfentanil
- Fentanyl
- Remifentanil
How often are fentanyl patches changed?
Every 72 hours
Which is more sedating and acts for longer, methadone or morphine?
- Methadone is less sedating than morphine and acts for longer periods.
What is the maximum times of administration for methadone in prolonged use?
Should not be administered more often than twice daily to avoid the risk of accumulation and opioid overdosage
Which opioid has a a similar profile to morphine and is commonly used as a second-line drug if morphine is not tolerated or does not control the pain?
Oxycodone
Which other opioid other than buprenorphine has partial agonist properties?
Pentazocine
It is not recommended and, in particular, should be avoided after myocardial infarction as it may increase pulmonary and aortic blood pressure as well as cardiac work.
Which indication is pethidine used in?
It is used for analgesia in labour; however, other opioids, such as morphine or diamorphine hydrochloride, are often preferred for obstetric pain.
Which two mechanism does Tapentadol (opioid work by)?
It is an opioid-receptor agonist and it also inhibits noradrenaline reuptake. Nausea, vomiting, and constipation are less likely to occur with tapentadol than with other strong opioid analgesics.
Which two mechanism does Tramadol (opioid work by)?
Tramadol hydrochloride produces analgesia by two mechanisms: an opioid effect and an enhancement of serotonergic and adrenergic pathways. It has fewer of the typical opioid side-effects (notably, less respiratory depression, less constipation and less addiction potential); psychiatric reactions have been reported.
Name some weak opioids?
Codeine
Dihydrocodeine
Meptazinol
What is the effect if benzodiazepines or benzo like drugs are co-prescribed with methadone?
The respiratory effect of methadone may be delayed
Is codeine CI in patients of any age who are known to be CYP2D6 …. metabolisers?
CYP2D6 ultra rapid metabolisers.
What are the signs of opioid toxicity?
- reduced consciousness
- lack of appetite
- somnolence
- constipation
- respiratory depression
‘pin-point’ pupils - nausea
- vomiting
What MHRA warning has been given about codeine use in children?
- Not to be used in children under 12
- Not to be used in children aged 12-18 who have problems with breathing
What advice can be given on where to apply fentanyl patches?
Apply to dry, non-irritated, non-irradiated, non-hairy skin on torso or upper arm removing after 72 hours and siting replacement patch on a different area (avoid using the same area for several days).
Do cluster headaches respond well to standard analgesics?
No they do not
What is the drug treatment of choice for cluster headaches?
Sumatriptan given by subcutaneous injection is the drug pf choice
If an injection is unsuitable, sumatriptan nasal spray or zolmitriptan nasal spray [both unlicensed use] may be used
Alternatively, 100% oxygen at a rate of 10–15 litres/minute for 10–20 minutes is useful in aborting an attack.
Which drug class does pizotifen belong to?
It is a sedating-antihistamine
what are the indications of pizotifen?
Prevention of vascular headache prevention of classical migraine common migraine prevention of cluster headaches Prophylaxis of migraine
What is migraine?
Migraine is a common type of primary headache disorder. It occurs more commonly in women than in men, and is characterised by recurrent attacks of typically moderate to severe headaches that usually last between 4–72 hours.
Does migraine usually cause headache on one side or both sides?
he headache is usually unilateral, pulsating, aggravated by routine physical activity, and may be severe enough to impact or prevent daily activities.
What is migraine usually associated with?
It is frequently accompanied by nausea and vomiting, photophobia and phonophobia, or both.
what sub groups is migraine subdivided into?
Migraine with or without aura, and it defined as either episodic or chronic
What does migraine with aura consist of?
Migraine with aura consists of visual symptoms (zigzag or flickering lights, spots, lines, or loss of vision), sensory symptoms (pins and needles, or numbness), or dysphasia, which usually precede the onset of headache. Symptoms usually develop gradually and resolve within 1 hour.
How many days of headaches defines episodic migraine (low and high) and chronic migraine?
Episodic migraine is defined as headache which occurs on less than 15 days per month, and can be further subdivided into low frequency (1–9 days per month) and high frequency (10–14 days per month). Chronic migraine is defined as headache which occurs on at least 15 days per month and has the characteristics of a migraine headache on at least 8 days per month for greater than 3 months.
For some women what may be a trigger for migraine?
In some women, the drop in oestrogen levels just before menstruation is a trigger for migraine, with symptoms generally occurring from two days before the start of bleeding up until three days after
What is medication-overuse headache (complication of migraine)?
the frequent use of acute treatment for migraine increases the frequency and intensity of headache, and can become the cause of the headache.
What lifestyle advice can be given for migraines?
Patients should be encouraged to eat regular meals, and to maintain adequate hydration, sleep and exercise. Other potential triggers include stress, relaxation after stress, some foods and drinks, and bright lights. Known triggers should be avoided; keeping a headache diary may be useful to identify potential triggers and should be continued for a minimum of 8 weeks.
For treatment of acute migraine - to reduce risk of developing medication-overuse headache, treatment should ideally be restricted to how many days per week?
- ideally restricted to 2 days per week and patients should be advised of the risk of developing medication over use headaches.
What drug class is 5HT1 receptor agonists?
(‘triptan)
What is the monotherapy recommended for acute migrains?
- Aspirin or
- Ibuprofen or
- 5HT1 receptor agonist (triptans)
When should a triptan be taken, timing wise?
should be taken as soon as the patient knows that they are developing a migraine (start of headache phase).
how about in patients who have migraines with aura - when are they advised to take their 5HT1 receptor agonist (Triptans)?
it is recommended that 5HT1-receptor agonists are taken at the start of the headache and not at the start of the aura (unless the aura and headache start at the same time).
