Difference between Antipyretic and Analgesic

There is a common underlying mechanism that manifests itself in inflammation, discomfort, and fever. As a result, medications used to treat these conditions are frequently interchangeable.

An analgesic is a medicine that reduces pain without affecting awareness, stopping nerve impulse transmission, or dramatically changing sensory experience. It is common practise to use an antipyretic while dealing with a fever. They have a cooling effect on the body.

Both narcotic and opioid analgesics exist, although they serve different purposes. Analgesic and fever-reducing medicines are examples of non-narcotic analgesics.

What is an Antipyretic Medicine?

Medications called antipyretics are used to bring down a high temperature. They prevent the hypothalamus from releasing prostaglandins, which would otherwise raise core body temperature. Risks of complications, dehydration, and overall worsening of the body's state are concealed by the high temperature, regardless of the reason. Antipyretics are used in addition to the standard care that focuses on resolving the underlying causes of the fever. Because of their versatility, antipyretics are among the most often prescribed medications.

The following agents, which are also non-narcotic analgesics, are among the most often used antipyretics −

• Paracetamol, the fastest acting and safest antipyretic for kids and pregnant women alike;

• Widespread therapeutic application of acetylsalicylic acid due to its several functions (anti-inflammatory action, analgesic effect, platelet anti-aggregation agent);

• Commonly used for its painkilling and fever-reducing effects, ibuprofen is a wonder medication.

If you want to address the underlying reasons of the fever, you need to know what triggered it in the first place.

Fever can be a symptom of −

• Viral infections;

• Bacterial infections;

• Autoimmune diseases;

• Neoplastic diseases;

• Taking certain medicines, etc.

In rare cases, side effects, toxicity, and adverse drug interactions are possible. Treatment with ibuprofen can lead to damage to the gastrointestinal tract and kidneys, paracetamol in very rare cases leads to a low number of platelets in the blood, a reduced number of leukocytes with an increased chance of developing infections, anemia. Allergic reactions are possible.

What are Analgesics?

Analgesics are medications that suppress pain. They are of two main types −

• Non-narcotic analgesics, which relieve pain by reducing local inflammatory reactions;

• Opioid analgesics, which act on specific centers in the brain.

Some preparations combine non-narcotic and opioid analgesics to enhance the effect. Non-narcotic analgesics are widely used and are available without a prescription. They are used for short-term pain relief, mainly for moderate pain, such as headaches, arthritis, toothache, etc.

Non-narcotic analgesics include the following preparations, which also have an antipyretic effect

• Salicylic acid and its derivatives − acetylsalicylic acid (aspirin), sodium salicylate, salicylamide;

• Anilides − paracetamol, phenacetin, bucetin, propacetamol;

• Pyrazolones − metamizole sodium, phenazone, aminophenazone, nifenazone.

Unlike non-narcotic analgesics, opioids can be used for both short-term and long-term relief, and in severe pain. They have the ability to induce sleep. Opioid analgesics are often much more effective against pain, but can be addictive and are a source of greater risk of side effects. Therefore, they are usually the last resort to overcome the pain. They are only available by prescription.

The group of narcotic analgesics includes −

• Morphine

• Tilidine

• Codeine

Non-opioid analgesics act on the prostaglandin system, which is responsible for the onset of pain. They block the production of prostaglandins and thus act as painkillers. Opioid analgesics bind to cell receptors, mainly in the brain, spinal cord, and gastrointestinal tract.

Side effects are rare with non-narcotic analgesics and include damage to the gastrointestinal tract and kidneys, low number of platelets in the blood, a reduced number of leukocytes with an increased chance of developing infections, anemia, allergic reactions.

The main side-effects of opioid analgesics are observed in the digestive system and the central nervous system. Transient drowsiness may occur with the initial onset of opioid analgesics or with increasing dose. Constipation, nausea, and dizziness are very common at the beginning of opioid use, but they are usually temporary. Allergic reactions are possible.

Differences: Antipyretic and Analgesic

The following table highlights the major differences between Antipyretic and Analgesic medicines −

Characteristics	Antipyretic	Analgesic
Definition	Antipyretics are drugs that reduce fever.	Analgesics are drugs that reduce pain.
Mechanism of action	Antipyretics block the production of prostaglandins and cause the hypothalamus to stop the rise in body temperature caused by them.	Non-opioid analgesics block the production of prostaglandins and thus act as painkillers. Opioid analgesics bind to cell receptors, mainly in the brain, spinal cord, and gastrointestinal tract.
Use	Antipyretics are used to reduce fever caused by viral infections, bacterial infections, autoimmune diseases, neoplastic diseases, etc.	Analgesics are used to relieve pain in headache, toothache, renal colic, various inflammatory and rheumatic diseases, muscle pain, neuralgia, cancer pain, etc.
Side effects	In rare cases, side effects, toxicity, and adverse drug interactions are possible, including damage to the gastrointestinal tract and kidneys, low number of platelets in the blood, a reduced number of leukocytes with an increased chance of developing infections, anemia, allergic reactions.	Side effects are rare with non-narcotic analgesics (damage to the gastrointestinal tract and kidneys, low number of platelets in the blood, a reduced number of leukocytes with an increased chance of developing infections, anemia, allergic reactions). The main side-effects of opioid analgesics include transient drowsiness, constipation, nausea, and dizziness, etc.
Examples	Paracetamol, acetylsalicylic acid, ibuprofen, etc.	Paracetamol, acetylsalicylic acid, ibuprofen, morphine, tilidine, codeine, etc.

Conclusion

Antipyretic medicines are used for short-term treatment of fever, whereas non-narcotic analgesics are used for short-term pain relief. Opioids can be used for both short-term and long- term relief.