Antibiotics & Painkillers (AQA GCSE Combined Science: Trilogy: Biology): Revision Note

Antibiotics & painkillers

• There are two types of medication that an individual can take:

  • medicines that treat the cause of the disease, e.g. antibiotics

  • medicines that treat the symptoms of the disease, e.g. painkillers, which do not kill pathogens

• Antibiotics, such as penicillin, are medicines that help to cure bacterial disease by killing bacteria inside the body

Using antibiotics

• Specific bacteria should be treated by specific antibiotics; this is important because

  • antibiotics that are known to be effective against certain bacteria can be used

  • it reduces the likelihood that bacteria will be exposed to multiple antibiotics, so reducing the risk that resistance will develop (see below)

• Antibiotics are ineffective against viruses, so should not be prescribed to treat viral diseases

  • Viruses reproduce inside body cells

  • It is difficult to develop drugs that kill viruses without also damaging the body’s tissues

Antibiotic resistance

• Deaths from infectious disease have been greatly reduced by the use of antibiotics in medical treatment

• However, since their discovery and widespread use, antibiotics have been overused, and antibiotic resistance has become a major concern

• This is a concern because current antibiotics no longer kill these bacteria, some diseases become more common or cannot be treated, and new antibiotics have to be developed, which takes time and money

Preventing development of resistant bacteria

• To reduce the number of bacteria that are becoming resistant to antibiotics:

  • doctors need to avoid the overuse of antibiotics, prescribing them only when needed – they may test the bacteria first to make sure that they prescribe the correct antibiotic

  • antibiotics should not be used in non-serious infections that the immune system will be able to deal with on its own

  • antibiotics should not be used for viral infections

  • antibiotic use should be reduced in industries such as agriculture – controls are now in place to limit their use in farming

Reducing the spread of resistant strains

• Good hygiene practices, such as handwashing and the use of hand sanitisers, have reduced the spread of resistant strains of bacteria, such as MRSA, in hospitals

• The isolation of infected patients also helps to prevent the spread of resistant strains, in particular in surgery wards where MRSA can infect surgical wounds