COLDCAP DAYTIME CAPSULES

Indications

• Mild to moderate pain
• Fever
• Headaches
• Muscle aches
• Arthritis
• Backaches
• Toothaches
• Colds

Dosage

Adults: For adults, the typical dosage is 500 mg to 1 g every 4 to 6 hours, with a maximum daily limit of 4 g. In cases of intravenous administration, the dosage is 15 mg/kg every

Mechanism of action

Paracetamol is thought to exert its analgesic effects by inhibiting cyclo-oxygenase (COX) enzymes, specifically COX-1 and COX-2, which are involved in the synthesis of prostaglandins responsible for pain sensation. Unlike most NSAIDs, paracetamol does not exhibit peripheral anti-inflammatory effects. Its antipyretic action is believed to result from direct action on heat-regulating centers in the brain, leading to peripheral vasodilation and sweating.

Pharmacodynamics

Paracetamol has been shown to have both antipyretic and analgesic effects, lacking any significant anti-inflammatory activity. It does not interfere with platelet aggregation or disrupt hemostasis, making it a safer option for individuals at risk of bleeding. Allergic reactions to paracetamol are rare. The drug does not affect uric acid secretion or acid-base balance when used at recommended doses.

Pharmacokinetics

Paracetamol is rapidly absorbed from the gastrointestinal tract, with peak plasma concentrations typically occurring within 30 to 60 minutes after oral administration. It is primarily metabolized in the liver via conjugation with glucuronide and sulfate, with a minor pathway involving cytochrome P450 enzymes. The elimination half-life ranges from 1 to 4 hours, with renal excretion of metabolites as the primary route of elimination.

Adverse effects

• Nausea and vomiting
• Liver injury
• Renal damage
• Hypersensitivity reactions
• Flushing
• Hypotension
• Anorectal erythema
• Angioedema
• Agranulocytosis
• Thrombocytopenia
• Leukopenia
• Severe cutaneous adverse reactions (SCARs)

Interactions

• Increased risk of methaemoglobinaemia with topical prilocaine
• Increased risk of methaemoglobinaemia with topical anaesthetics
• Increased anticoagulant effect with coumarins
• Increased risk of hepatotoxicity with imatinib
• Decreased exposure with rifampicin
• Decreased exposure with pitolisant

Precautions

• Monitor patients with liver disease or heavy alcohol use for increased risk of hepatotoxicity
• Adjust doses in patients taking enzyme-inducing antiepileptic medications
• Use caution in patients with renal impairment
• Clinical judgement is required for dose adjustment in weight-based dosing

Pregnancy

Paracetamol is generally considered safe to use during pregnancy for pain and fever relief, but should be used at the lowest effective dose for the shortest duration necessary.

Breast-feeding

Paracetamol is excreted in breast milk in small amounts and is considered safe for use while breastfeeding.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Oral tablets (500 mg)
• Oral suspension (120 mg/5 mL, 500 mg/5 mL)
• Rectal suppositories (various strengths)
• Intravenous infusion (various strengths)

Indications

• Management of apnea in premature infants
• Enhancement of alertness and performance
• Treatment of headaches, often in combination with analgesics

Dosage

Children: For neonates with apnea of prematurity, the usual dose of caffeine citrate is 20 mg/kg as a loading dose, followed by 5 to 10 mg/kg once daily. For precise pediatric dosing recommendations, consult the BNF for Children.

Adults: The typical adult dose for caffeine varies based on the indication. For acute use, 100 to 200 mg can be taken as needed, not exceeding 400 mg per day. For specific medical indications, refer to the BNF for detailed dosing guidelines.

Mechanism of action

Caffeine's mechanism of action is complex and involves the inhibition of nucleotide phosphodiesterase enzymes, antagonism of adenosine receptors, and regulation of calcium handling in cells. It stimulates the central nervous system by blocking adenosine receptors, which enhances respiratory drive and increases alertness. Additionally, caffeine promotes lipolysis and has effects on cardiovascular contractility.

Pharmacodynamics

Caffeine stimulates the central nervous system, leading to increased alertness and decreased drowsiness. It also relaxes smooth muscle, enhances cardiac muscle contraction, promotes gastric acid secretion, and increases gastrointestinal motility. Caffeine may act as a mild diuretic and is often used in combination with analgesics to relieve headaches.

Pharmacokinetics

Caffeine is rapidly absorbed from the gastrointestinal tract and reaches peak plasma concentrations within 30 to 120 minutes after ingestion. It is metabolized primarily by the liver enzyme cytochrome P450 1A2. The half-life of caffeine varies significantly among individuals, ranging from 3 to 7 hours, depending on factors such as age, liver function, and concurrent medications.

Adverse effects

• Restlessness
• Agitation
• Insomnia
• Increased heart rate
• Gastrointestinal disturbances
• Headache

Interactions

• caffeinecitrate+adenosine: Unknown (decreases efficacy)
• caffeinecitrate+antiarrhythmics: Unknown (decreases efficacy)

Precautions

• Caution in patients with cardiovascular disorders
• Use with caution in individuals with anxiety disorders
• Monitor for potential dependence with chronic use

Pregnancy

Caffeine should be used cautiously during pregnancy due to potential risks to the fetus, including increased heart rate and reduced placental blood flow.

Breast-feeding

Caffeine is excreted in breast milk; mothers should limit intake to avoid potential effects on the infant, such as irritability or sleep disturbances.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Caffeine citrate injection
• Caffeine tablets
• Caffeine oral solution

Indications

• Nasal congestion due to colds
• Allergic rhinitis
• Sinusitis
• Eustachian tube dysfunction

Dosage

Children: Refer to BNF for Children for specific dosing recommendations.

Adults: Refer to BNF or local guidelines for specific dosing recommendations.

Mechanism of action

Pseudoephedrine primarily functions as an alpha-adrenergic agonist. It stimulates alpha-1 adrenergic receptors on vascular smooth muscle, leading to vasoconstriction. This action decreases blood flow to the nasal mucosa, resulting in reduced edema and congestion.

Pharmacodynamics

The pharmacodynamic effects of pseudoephedrine include its ability to alleviate nasal congestion and pressure. By reducing nasal mucosal swelling and promoting airflow, pseudoephedrine provides symptomatic relief in conditions associated with upper respiratory tract congestion. Its effects typically appear within 30 minutes and can last for several hours.

Pharmacokinetics

Pseudoephedrine is well absorbed after oral administration. It is metabolized in the liver and has a half-life of approximately 6 hours. The drug is excreted primarily in the urine, with about 55% of a dose being eliminated unchanged. Renal function can affect the elimination of pseudoephedrine, necessitating dosage adjustments in patients with renal impairment.

Contra-indications

• Severe hypertension
• Severe coronary artery disease
• Concurrent use of monoamine oxidase inhibitors (MAOIs)
• Hypersensitivity to pseudoephedrine or any component of the formulation

Adverse effects

• Insomnia
• Nervousness
• Dizziness
• Increased blood pressure
• Tachycardia
• Dry mouth
• Nausea
• Headache

Interactions

• Monoamine oxidase inhibitors (MAOIs) may increase the risk of hypertensive crisis
• Other sympathomimetics may exacerbate cardiovascular side effects
• Antihypertensive agents may have reduced effectiveness

Precautions

• Use with caution in patients with hypertension, heart disease, diabetes, hyperthyroidism, or prostatic hypertrophy
• Monitor blood pressure regularly during treatment
• Use in caution in elderly patients

Pregnancy

Pseudoephedrine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Consult healthcare provider for guidance.

Breast-feeding

Pseudoephedrine is excreted in breast milk; caution is advised when administering to nursing mothers. Consult healthcare provider.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Tablets
• Extended-release tablets
• Liquid formulations
• Combination products with antihistamines or analgesics

Mechanism of action

The mechanism of action of caffeine is complex, as it impacts several body systems, which are listed below. The effects as they relate to various body systems are described as follows: **General and cellular actions** Caffeine exerts several actions on cells, but the clinical relevance is poorly understood. One probable mechanism is the inhibition of nucleotide phosphodiesterase enzymes, adenosine receptors, regulation of calcium handling in cells, and participates in adenosine receptor antagonism. Phosphodiesterase enzymes regulate cell function via actions on second messengers cAMP and cGMP. This causes lipolysis through activation of hormone-sensitive lipases, releasing fatty acids and glycerol. **Respiratory** The exact mechanism of action of caffeine in treating apnea related to prematurity is unknown, however, there are several proposed mechanisms, including respiratory center stimulation in the central nervous system, a reduced threshold to hypercapnia with increased response, and increased consumption of oxygen, among others. The blocking of the adenosine receptors enhances respiratory drive via an increase in brain medullary response to carbon dioxide, stimulating ventilation and respiratory drive, while increasing contractility of the diaphragm. **Central nervous system** Caffeine demonstrates antagonism of all 4 adenosine receptor subtypes (A1, A2a, A2b, A3) in the central nervous system. Caffeine's effects on alertness and combatting drowsiness are specifically related to the antagonism of the A2a receptor. **Renal system** Caffeine has diuretic effects due to is stimulatory effects on renal blood flow, increase in glomerular filtration, and increase in sodium excretion. **Cardiovascular system** Adenosine receptor antagonism at the A1 receptor by caffeine stimulates inotropic effects in the heart. Blocking of adenosine receptors promotes catecholamine release, leading to stimulatory effects occurring in the heart and the rest of the body. In the blood vessels, caffeine exerts direct antagonism of adenosine receptors, causing vasodilation. It stimulates the endothelial cells in the blood vessel wall to release nitric oxide, potentiating blood vessel relaxation. Catecholamine release, however, antagonizes this and exerts inotropic and chronotropic effects on the heart, ultimately leading to vasoconstriction. Finally, caffeine is shown to raise systolic blood pressure measurements by 5 to 10 mmHg when it is not taken regularly, versus no effect in those who consume it regularly. The vasoconstricting effects of caffeine are beneficial in migraines and other types of headache, which are normally caused by vasodilation in the brain. Caffeine competitively inhibits phosphodiesterase, the enzyme that degrades cyclic 3',5'-adenosine monophosphate (AMP). Increased levels of intracellular cyclic AMP mediate most of caffeine's pharmacologic actions. Caffeine stimulates all levels of the CNS... Caffeine's cortical effects are milder and of shorter duration than those of amphetamines. In slightly larger doses, caffeine stimulates medullary, vagal, vasomotor, and respiratory centers, promoting bradycardia, vasoconstriction, and increased respiratory rate. Caffeine constricts cerebral vasculature. In contrast, the drug directly dilates peripheral blood vessels...

Pharmacodynamics

Caffeine stimulates the central nervous system (CNS), heightening alertness, and sometimes causing restlessness and agitation. It relaxes smooth muscle, stimulates the contraction of cardiac muscle, and enhances athletic performance. Caffeine promotes gastric acid secretion and increases gastrointestinal motility. It is often combined in products with analgesics and ergot alkaloids, relieving the symptoms of migraine and other types of headaches. Finally, caffeine acts as a mild diuretic.

Mechanism of action

According to its FDA labeling, acetaminophen's exact mechanism of action has not been fully established - despite this, it is often categorized alongside NSAIDs (non-steroidal anti-inflammatory drugs) due to its ability to inhibit the cyclo-oxygenase (COX) pathways. It is thought to exert central actions which ultimately lead to the alleviation of pain symptoms. One theory is that acetaminophen increases the pain threshold by inhibiting two isoforms of cyclo-oxygenase, COX-1 and COX-2, which are involved in prostaglandin (PG) synthesis. Prostaglandins are responsible for eliciting pain sensations. Acetaminophen does not inhibit cyclooxygenase in peripheral tissues and, therefore, has no peripheral anti-inflammatory effects. Though acetylsalicylic acid (aspirin) is an irreversible inhibitor of COX and directly blocks the active site of this enzyme, studies have shown that acetaminophen (paracetamol) blocks COX indirectly. Studies also suggest that acetaminophen selectively blocks a variant type of the COX enzyme that is unique from the known variants COX-1 and COX-2. This enzyme has been referred to as _COX-3_. The antipyretic actions of acetaminophen are likely attributed to direct action on heat-regulating centers in the brain, resulting in peripheral vasodilation, sweating, and loss of body heat. The exact mechanism of action of this drug is not fully understood at this time, but future research may contribute to deeper knowledge. Although further investigation is warranted, the active metabolite of acetaminophen (AM404) was shown to interact with several molecular targets, including the Ca_v3.2 calcium channel, the cannabinoid CB1 receptors, TRPV1 receptors, and Na_v1.8 and Na_v1.7 channels. Acetaminophen produces analgesia and antipyresis by a mechanism similar to that of salicylates. Unlike salicylates, however, acetaminophen does not have uricosuric activity. There is some evidence that acetaminophen has weak anti-inflammatory activity in some nonrheumatoid conditions (e.g., in patients who have had oral surgery). ... Acetaminophen lowers body temperature in patients with fever but rarely lowers normal body temperature. The drug acts on the hypothalamus to produce antipyresis; heat dissipation is increased as a result of vasodilation and increased peripheral blood flow. The effects of acetaminophen on cyclooxygenase activity have not been fully determined. Acetaminophen is a weak, reversible, isoform-nonspecific cyclooxygenase inhibitor at dosages of 1 g daily. The inhibitory effect of acetaminophen on cyclooxygenase-1 is limited, and the drug does not inhibit platelet function. Therapeutic doses of acetaminophen appear to have little effect on cardiovascular and respiratory systems; however, toxic doses may cause circulatory failure and rapid, shallow breathing. Acetaminophen (N-acetyl-p-aminophenol (APAP)) is the most common antipyretic/analgesic medicine worldwide. If APAP is overdosed, its metabolite, N-acetyl-p-benzo-quinoneimine (NAPQI), causes liver damage. However, epidemiological evidence has associated previous use of therapeutic APAP doses with the risk of chronic obstructive pulmonary disease (COPD) and asthma. The transient receptor potential ankyrin-1 (TRPA1) channel is expressed by peptidergic primary sensory neurons. Because NAPQI, like other TRPA1 activators, is an electrophilic molecule, /the researchers/ hypothesized that APAP, via NAPQI, stimulates TRPA1, thus causing airway neurogenic inflammation. NAPQI selectively excites human recombinant and native (neuroblastoma cells) TRPA1. TRPA1 activation by NAPQI releases proinflammatory neuropeptides (substance P and calcitonin gene-related peptide) from sensory nerve terminals in rodent airways, thereby causing neurogenic edema and neutrophilia. Single or repeated administration of therapeutic (15-60 mg/kg) APAP doses to mice produces detectable levels of NAPQI in the lung, and increases neutrophil numbers, myeloperoxidase

Pharmacodynamics

Animal and clinical studies have determined that acetaminophen has both antipyretic and analgesic effects. This drug has been shown to lack anti-inflammatory effects. As opposed to the _salicylate_ drug class, acetaminophen does not disrupt tubular secretion of uric acid and does not affect acid-base balance if taken at the recommended doses. Acetaminophen does not disrupt hemostasis and does not have inhibitory activities against platelet aggregation. Allergic reactions are rare occurrences following acetaminophen use.