OTC misuse Flashcards
(28 cards)
What is misuse?
- using medicine not as intended
- using medicine for recreational purposes
- overusing medicine
- using medicine in a dependent way
What is the difference between intentional and unintentional misuse?
- some misuses are unintentional e.g. taking higher than recommended doses to elicit beneficial medical effect
- some misuse is intentional and relates to obtaining euphoric effects, laxative abuse, prevent withdrawal symptoms when drugs of choice are unavailable
What is the general spectrum of OTC misuse?
they usually start off unintentionally, then become intentional misuse
what are examples of unintentional misuse?
- over use, use for too long, use in inappropriate patient, drug interactions
- these can result in severe ADRs from other ingredients e.g. paracetamol toxicity, GI problems with ibuprofen
- often arise due to lack of info to consumers
What are other causes for unintentional misuse?
- advertising/labeling may ‘promote’ misuse
- once informed, patients usualyl respond positively to making changes
- can also lead to intentional misuse
What are the characteristics of intentional misuse?
- often covert
- may shop around to avoid suspicion
- might be at a higher dose than recommended
- may be fore recreational purposes
- may be in conjunction with use of illicit drugs
- maybe as a source of precursor
- may lead to negative health outcomes
What are the consequences of misuse?
primary drug:
- ADRs
- electrolyte imbalance (laatives)
- dependence
- negative health consequences including death.
additional ingredient
- GI irritation (NSAIDs)
- rebound problems
- hypokalaemia/acidosis (ibuprofen)
- liver toxicity (paracetamol)
Why are OTC ‘herbal’ and alternative medicines not any safer to misuse?
- they have a perception that they are natural
- often lack clarity on contents
- rarely evidence to back up any claims
What is Ma Huang?
- contains ephedrine, misused as stimulant
- sometimes also with norpseudoephedrine (more toxic)
- there is no way of knowing how much ephedrine it contains
What are the resutls of taking Ma Huang?
- heart disease
- inflammation of liver and heart
- unusual form of kidney stones that contain ephedrine
- certain preparations of ephedra may be toxic to nervous system
What can occur with ephdra and MOAi?
serious drug interaction
What kinds of drugs can get abused?
opiates antihistamines sympathomimetics performance enhancers laxatives
What are opiates used for?
-included in compound analgesics as codeine
-homebake
-used for:
pain relief,
prevention of withdrawal when addicted to OTC,
euphoric effect,
prevent withdrawal symptoms when no morphine or heroin available
What are the effects of opiates?
euphoria, sedation, pinned pupils, respiratory depression
What are the effects of high doses of opiates?
respiratory depression
What other substances increase the overdose risk?
alcohol
other CNS depressants
What are the problems with codiene overuse?
other ingredients in OTC products:
ibuprofen = GI haemorrhage, perforated duodenal ulers, acute renal failure, hypokalaemia
Paracetamol= toxicity, death
Why is dextromephorphan misused?
- primarily used in cough medicines and historically believed to have no euphoric effect
- misused primarily by younger adolescnets
- non opiod analogue of codiene
- metabolised to dextrphan which antagonises NMDA receptors which might result in dissociative effects sought by abusers
What are the effects of dextromephorphan?
initially stimulant effects
-feelings of dissociation, euphoria, ataxia, restlessness, loss of concentration at doses > 2mg/kg
- antagonises 5-HT receptors may lead to serotonin syndrome?
- co ingestion with pseudoephedrine and chlorpheniramine can cause tachycardia, hypertension, hyperthermia, mydriasis and urinary retention
How are sedating antihistamines used?
- included in many sleep aids e.g. diphenhydramine, cyclizine, dimenhydrinate
- possibly used for antmuscarinic effects
- nytol most misused in a scottish study,
- often used in conjunction with alcohol
- may be used to ‘come down’ from cocaine and other stimulants
How are sympathomimetics used?
e. g. pseudoephedrine
- may be misused for psychoactive effect as it is a stimulant
- performance enhancer: found in sports people, long distance lorry drivers
- metamphetamine precursor
- has potential for dependence if used over long periods
What are the effects of sympathomimetics?
- peripheral vasoconsctriction,
- cardiac stimulation
- increased blood pressure
- increased heart rate
What are the adverse effects of sympathomimetics on the CNS?
- nervousness
- anxiety
- tremor
- weakness
- irritability
- insomnia
these increase with higher doses
What are the effects of sympathomimetic overdose?
- nausea
- vomiting
- fever
- palpitations
- tachycardia
- hypertension
- paranoid psychosis
- respiratory depression
- convulsions
- comas
