Fiorinal w/Codeine

Fiorinal w/Codeine Uses, Dosage, Side Effects, Food Interaction and all others data.

By decreasing platelet aggregation, Aspirin inhibits thrombus formation on the arterial side of the circulation, where thrombi are formed by platelet aggregation and anticoagulants have little effect. Aspirin is the analgesic of choice for headache, transient musculoskeletal pain and dysmenorrhoea. It has anti-inflammatory and antipyretic properties, which may be useful. Enteric coating reduces the intestinal disturbance and gastrointestinal ulceration due to aspirin.

Effects on pain and fever

Acetylsalicylic acid disrupts the production of prostaglandins throughout the body by targeting cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) . Prostaglandins are potent, irritating substances that have been shown to cause headaches and pain upon injection into humans. Prostaglandins increase the sensitivity of pain receptors and substances such as histamine and bradykinin. Through the disruption of the production and prevention of release of prostaglandins in inflammation, this drug may stop their action at pain receptors, preventing symptoms of pain. Acetylsalicylic acid is considered an antipyretic agent because of its ability to interfere with the production of brain prostaglandin E1. Prostaglandin E1 is known to be an extremely powerful fever-inducing agent .

Effects on platelet aggregation

Butalbital, or 5-allyl-5-isobutylbarbituric acid, is a derivative of barbituric acid which the hydrogens at position 5 are substituted by an allyl group and an isobutyl group. It is a short-to-intermediate acting member of barbiturates that exhibit muscle-relaxing and anti-anxiety properties that produce central nervous system (CNS) depression that ranges from mild sedation to general anesthesia. Butalbital has a low degree of selectivity and a narrow therapeutic index. Typically indicated to manage tension (or muscle contraction) headaches, butalbital is often combined with one or more therapeutic agents, such as acetylsalicylic acid, acetaminophen, aspirin, and caffeine. There have not been clinical trials that evaluate the clinical efficacy of butalbital in migraines thus it is not indicated for such condition. As with other barbiturates, butalbital carries a risk of abuse or misuse potential, intoxication, hangover, tolerance, dependence, and overdosage possibly leading to death. Butalbital‐containing analgesics can also produce a drug‐induced headache in addition to tolerance and dependence. Due to these risks, the use of butalbital-containing combination products is typically limited for use only in cases where other medications are deemed ineffective and such usage is advised to be carefully monitored.

Butalbital is a short to intermediate-acting barbiturate that reversibly depresses the activity of excitable tissues, including the central nervous system in a nonselective manner. Barbiturates exhibit muscle-relaxing and anti-anxiety properties and they are capable of producing all levels of CNS mood alteration from excitation to mild sedation, hypnosis, and deep coma. The sedative dose of butalbital in nontolerant individuals is 5-100 mg and the hypnotic dose is 100-200 mg. Pain perception and reaction are relatively unimpaired until the moment of unconsciousness. In some cases, an unwanted paradoxical response of excitement may be observed instead of sedation with barbiturate treatment, which may be due to their depressant effects on inhibitory centers of the CNS. At sufficiently high therapeutic doses, barbiturates induce anesthesia; however, barbiturates are reported to lose their effectiveness for sleep induction and sleep maintenance after 2 weeks. Barbiturates are habit-forming; they can produce tolerance and both dependence and addiction, which is partly explained by decreased drug concentration at the site of action due to enhanced drug metabolism by induced enzymes, or to cellular adaptive changes. In addition, butalbital may lead to analgesic overuse headache.

While butalbital is expected to mediate similar actions as other members of the barbiturate drug class, the effects of butalbital in isolation are not well understood. It is suggested that butalbital is added in combination products to antagonize the unwanted central stimulating effect of stimulatory ingredients such as caffeine. Butalbital may decrease blood pressure and heart rate when administered at sedative and hypnotic doses.

Caffeine is a drug of the methylxanthine class used for a variety of purposes, including certain respiratory conditions of the premature newborn, pain relief, and to combat drowsiness. Caffeine is similar in chemical structure to Theophylline and Theobromine. It can be sourced from coffee beans, but also occurs naturally in various teas and cacao beans, which are different than coffee beans. Caffeine is also used in a variety of cosmetic products and can be administered topically, orally, by inhalation, or by injection.

The caffeine citrate injection, used for apnea of the premature newborn, was initially approved by the FDA in 1999. According to an article from 2017, more than 15 million babies are born prematurely worldwide. This correlates to about 1 in 10 births. Premature birth can lead to apnea and bronchopulmonary dysplasia, a condition that interferes with lung development and may eventually cause asthma or early onset emphysema in those born prematurely. Caffeine is beneficial in preventing and treating apnea and bronchopulmonary dysplasia in newborns, improving the quality of life of premature infants.

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.

The relief of pain (analgesia) is a primary goal for enhancing the quality of life of patients and for increasing the ability of patients to engage in day to day activities. Codeine, an opioid analgesic, was originally approved in the US in 1950 and is a drug used to decrease pain by increasing the threshold for pain without impairing consciousness or altering other sensory functions. Opiates such as codeine are derived from the poppy plant, Papaver somniferum (Papaveraceae).

Codeine is utilized as a central analgesic, sedative, hypnotic, antinociceptive, and antiperistaltic agent, and is also recommended in certain diseases with incessant coughing.

General effects

Trade Name Fiorinal w/Codeine
Generic Acetylsalicylic acid + butalbital + caffeine + codeine
Type Oral
Therapeutic Class
Manufacturer
Available Country United States
Last Updated: September 19, 2023 at 7:00 am
Fiorinal w/Codeine
Fiorinal w/Codeine

Uses

Aspirin is used for its antiplatelet activity in the initial treatment of cardiovascular disorders such as angina pectoris and myocardial infarction and for the prevention of cardiovascular events in a variety of conditions or procedures for patients at risk.

  • Aspirin is used as part of the initial treatment of unstable angina.
  • It is given in the early treatment of myocardial infarction.
  • It may also be of some benefit in the initial treatment of acute ischaemic stroke.
  • It is of value for the secondary prevention of cardiovascular events in patients with stable or unstable angina or those with acute or prior myocardial infarction.
  • Aspirin reduces the risk of future serious vascular events, including stroke, in patients who have already suffered an ischaemic stroke or transient ischaemic attack.
  • It is of use in the long-term management of atrial fibrillation, for the prevention of stroke in patients with contraindications to warfarin or if there are no other risk factors for stroke.
  • It is recommended for use in preventing thrombotic complications associated with procedures such as angioplasty and coronary bypass grafting.

Butalbital is a barbiturate drug used for symptomatic treatment of tension-type headache in various combinations with acetaminophen, aspirin, caffeine, and codeine.

Indicated for the management of the symptom complex of tension (or muscle contraction) headache, when other non-opioid analgesics and alternative treatments are inadequate, in various combinations with acetaminophen, aspirin, caffeine, and codeine .

Caffeine is a stimulant present in tea, coffee, cola beverages, analgesic drugs, and agents used to increase alertness. It is also used in to prevent and treat pulmonary complications of premature birth.

Caffeine is indicated for the short term treatment of apnea of prematurity in infants and off label for the prevention and treatment of bronchopulmonary dysplasia caused by premature birth. In addition, it is indicated in combination with sodium benzoate to treat respiratory depression resulting from an overdose with CNS depressant drugs. Caffeine has a broad range of over the counter uses, and is found in energy supplements, athletic enhancement products, pain relief products, as well as cosmetic products.

Codeine is an opioid analgesic used to treat moderate to severe pain when the use of an opioid is indicated.

Codeine sulfate is a form of this drug that is commonly used. It is available in tablet form and indicated for the relief of mild to moderately severe pain, where the use of an opioid analgesic is appropriate .

The solution form is used by itself or combined in a syrup with other drugs and is used as a cough suppressant in adults aged 18 and above , .

Fiorinal w/Codeine is also used to associated treatment for these conditions: Acute Coronary Syndrome (ACS), Anxiety, Arthritis, Atherothrombotic cerebral infarction, Cardiovascular Disease (CVD), Cardiovascular Events, Cardiovascular Mortality, Colorectal Adenomas, Colorectal Cancers, Common Cold, Coronary artery reocclusion, Death, Dyspeptic signs and symptoms, Fever, Flu Like Symptom, Flu caused by Influenza, Headache, Heterozygous Familial Hypercholesterolemia, Inflammation, Juvenile Idiopathic Arthritis (JIA), Kawasaki Syndrome, Major Adverse Cardiovascular and Cerebrovascular Events (MACCE), Migraine, Morbidity, Mucocutaneous Lymph Node Syndrome, Muscle Contraction, Myocardial Infarction, Myocardial Infarction (MI), first occurrence, Neuralgia, Pain, Pain caused by Common Cold, Pain, Menstrual, Pericarditis, Polycythemia Vera (PV), Preeclampsia, Rheumatic Pain, Rheumatism, Rheumatoid Arthritis, Rhinosinusitis, Severe Pain, Soreness, Muscle, Spondyloarthropathies, Stroke, Systemic Lupus Erythematosus (SLE), Tension Headache, Thromboembolism, Toothache, Transient Ischemic Attack, Venous Thromboembolism, Acute Inflammation, Atherothrombotic events, Death by myocardial infarction, Moderate Pain, Thrombotic events, Antiplatelet Therapy, Hemodialysis Treatment, Secondary PreventionTension HeadacheBronchopulmonary Dysplasia (BPD), Common Cold, Dark circles under eyes, Dyspepsia, Fatigue, Fever, Flu caused by Influenza, Headache, Migraine, Pain, Pain, Acute, Pain, Menstrual, Primary apnea of premature newborns, Respiratory Depression, Rheumatic Pain, Somnolence, Soreness, Muscle, Tension Headache, Toothache, Moderate Pain, Analgesia, Antacid therapy, Athletic PerformanceCommon Cold, Cough, Flu caused by Influenza, Mild pain, Pain, Severe Pain, Dry cough, Moderate Pain, Upper respiratory symptoms, Airway secretion clearance therapy

How Fiorinal w/Codeine works

Acetylsalicylic acid (ASA) blocks prostaglandin synthesis. It is non-selective for COX-1 and COX-2 enzymes . Inhibition of COX-1 results in the inhibition of platelet aggregation for about 7-10 days (average platelet lifespan). The acetyl group of acetylsalicylic acid binds with a serine residue of the cyclooxygenase-1 (COX-1) enzyme, leading to irreversible inhibition. This prevents the production of pain-causing prostaglandins. This process also stops the conversion of arachidonic acid to thromboxane A2 (TXA2), which is a potent inducer of platelet aggregation . Platelet aggregation can result in clots and harmful venous and arterial thromboembolism, leading to conditions such as pulmonary embolism and stroke.

It is important to note that there is 60% homology between the protein structures of COX-1 and COX-2. ASA binds to serine 516 residue on the active site of COX-2 in the same fashion as its binding to the serine 530 residue located on the active site of COX-1. The active site of COX-2 is, however, slightly larger than the active site of COX-1, so that arachidonic acid (which later becomes prostaglandins) manages to bypass the aspirin molecule inactivating COX-2 . ASA, therefore, exerts more action on the COX-1 receptor rather than on the COX-2 receptor . A higher dose of acetylsalicylic acid is required for COX-2 inhibition .

Butalbital is a CNS depressant that suppresses neuronal excitability, impulse conduction, and the release of neurotransmitters, similar to actions of other barbiturates. Barbiturates primarily mediate suppressive actions on polysynaptic neuronal responses by diminishing facilitation while enhancing inhibition. Inhibition occurs at GABAergic synapses that express GABA-A receptors, which are transmembrane chloride ion channels that bind an inhibitory neurotransmitter GABA, barbiturates, benzodiazepines, neurosteroids, and ethanol. Upon activation, GABA-A receptors allow Cl- influx and K+ efflux into the postjunctional terminal, resulting in inhibition of the postsynaptic neuron. It is suggested that barbiturates, including butalbital, enhances GABA binding to the GABA-A receptors by binding to the α+/β− interface in the intracellular domain (ICD) as an allosteric modulator. Additionally, barbiturates promote benzodiazepine binding to the receptor. Barbiturates potentiate GABA-induced increases in chloride conductance and depress voltage-activated calcium currents while prolonging the duration of GABA-induced chloride channel opening. Butalbital may also inhibit the excitatory effects mediated by AMPA receptors by reducing glutamate-induced depolarizations of the receptor. It is also proposed that barbiturates and opioids may potentiate the analgesic effects of each other when co-administered, although there are inconsistencies across preclinical data.

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.

Codeine is a selective agonist for the mu opioid receptor, but with a much weaker affinity to this receptor than morphine, a more potent opioid drug. Codeine binds to mu-opioid receptors, which are involved in the transmission of pain throughout the body and central nervous system , . The analgesic properties of codeine are thought to arise from its conversion to Morphine, although the exact mechanism of analgesic action is unknown at this time , .

Dosage

Fiorinal w/Codeine dosage

Pain, Inflammatory diseases and as Antipyretic: Aspirin 300 mg 1-3 tablets 6 hourly with a maximum daily dose of 4 g.

Thrombotic cerebrovascular or Cardiovascular disease: Aspirin 300 mg 1 tablet or Aspirin 75 mg 4 tablets daily.

After Myocardial infarction: Aspirin 75 mg 2 tablets daily for 1 month.

Following By-pass surgery: Aspirin 75 mg 1 tablet daily.

Side Effects

Side effects for usual dosage of Aspirin are mild including nausea, dyspepsia, gastrointestinal ulceration and bronchospasm etc.

Toxicity

Lethal doses

Acute oral LD50 values have been reported as over 1.0 g/kg in humans, cats, and dogs, 0.92 g/kg - 1.48 g/kg in albino rats, 1.19 g/kg in guinea pigs, 1.1 g/kg in mice, and 1.8 g/kg in rabbit models .

Acute toxicity

Salicylate toxicity is a problem that may develop with both acute and chronic salicylate exposure . Multiple organ systems may be affected by salicylate toxicity, including the central nervous system, the pulmonary system, and the gastrointestinal system. Severe bleeding may occur. In the majority of cases, patients suffering from salicylate toxicity are volume-depleted at the time of presentation for medical attention. Fluid resuscitation should occur immediately and volume status should be monitored closely. Disruptions in acid-base balance are frequent in ASA toxicity .

The acute toxicity of acetylsalicylic in animals has been widely studied. The signs of poisoning in rats from lethal doses are mild to severe gastroenteritis, hepatitis, nephritis, pulmonary edema, encephalopathy, shock and some toxic effects on other organs and tissues. Mortality has been observed following convulsions or cardiovascular shock. An important differentiating property between various animal species is the ability to vomit toxic doses. Humans, cats and dogs have this ability, but rodents or rabbits do not .

Chronic toxicity and carcinogenesis

Chronic ASA toxicity is frequently accompanied by atypical clinical presentations that may be similar to diabetic ketoacidosis, delirium, cerebrovascular accident (CVA), myocardial infarction (MI) or cardiac failure. Plasma salicylate concentrations should be measured if salicylate intoxication is suspected, even if there no documentation available to suggest ASA was ingested. In older age, nephrotoxicity from salicylates increases, and the risk of upper gastrointestinal hemorrhage is increased, with higher rates of mortality . It is also important to note that ASA toxicity may occur even with close to normal serum concentrations. Prevention of chronic ASA includes the administration of smallest possible doses, avoidance of concurrent use of salicylate drugs, and therapeutic drug monitoring. Renal function should be regularly monitored and screening for gastrointestinal bleeding should be done at regular intervals .

Chronic toxicity studies were performed in rodents. ASA was administered at doses measured to be 2 to 20 times the maximum tolerated clinical dose to mice for up to one year. Negative dose-related effects were seen. These include decreased mean survival time, decreased number of births and progeny reaching an appropriate age for weaning. No evidence of carcinogenesis was found in 1-year studies . At daily doses of 0.24 g/kg/day given for 100 days to albino rats, ASA led to signs to excessive thirst, aciduria, diuresis, drowsiness, hyperreflexia, piloerection, changes in respiration, tachycardia, followed by soft stools, epistaxis, sialorrhea, dacryorrhea and mortality during hypothermic coma in the second study month .

Use in pregnancy and lactation

While teratogenic effects were observed in animals nearly lethal doses, no evidence suggests that this drug is teratogenic in humans . It is advisable, however, to avoid ASA use the first and second trimester of pregnancy, unless it is clearly required. If acetylsalicylic acid containing drugs are ingested by a patient attempting to conceive, or during the first and second trimester of pregnancy, the lowest possible dose at the shortest possible duration should be taken . This drug is contraindicated in the 3rd trimester of pregnancy .

Reported oral TDLO (woman) is 400 mg/kg and subcutaneous LD50 in rat is 160 mg/kg. The lowest acute dose of butalbital alone associated with death in adults is 2.0 g. Symptoms of acute barbiturate poisoning include drowsiness, confusion, coma, respiratory depression, hypotension, and shock. Due to the CNS depressant effects, an overdose of barbiturates may lead to death. Barbiturates are also associated with withdrawal reactions, which may lead to death if severe.

The oral LD50 of caffeine in rats is 192 mg/kg. An acute fatal overdose of caffeine in humans is about 10–14 grams (equivalent to 150–200 mg/kg of body weight).

Caffeine overdose

In the case of caffeine overdose, seizures may occur, as caffeine is a central nervous system stimulant. It should be used with extreme caution in those with epilepsy or other seizure disorders. Symptoms of overdose may include nausea, vomiting, diarrhea, and gastrointestinal upset. Intoxication with caffeine is included in the World Health Organization’s International Classification of Diseases (ICD-10). Agitation, anxiety, restlessness, insomnia, tachycardia, tremors, tachycardia, psychomotor agitation, and, in some cases, death can occur, depending on the amount of caffeine consumed. Overdose is more likely to occur in individuals who do not consume caffeine regularly but consume energy drinks.

Overdose management

For a mild caffeine overdose, offer symptomatic treatment. In the case of a severe overdose, intubation for airway protection from changes in mental status or vomiting may be needed. Activated charcoal and hemodialysis can prevent further complications of an overdose and prevent absorption and metabolism. Benzodiazepine drugs can be administered to prevent or treat seizures. IV fluids and vasopressors may be necessary to combat hypotension associated with caffeine overdose. In addition, magnesium and beta blocking drugs can be used to treat arrhythmias that may occur, with defibrillation and resuscitation if the arrhythmias are lethal. Follow local ACLS protocols.

Oral LD50: 427 mg kg-1 (rat) .

Overdose/toxicity

Symptoms of opioid toxicity may include confusion, somnolence, shallow breathing, constricted pupils, nausea, vomiting, constipation and a lack of appetite. In severe cases, symptoms of circulatory and respiratory depression may ensue, which may be life-threatening or fatal , .

Teratogenic effects

This drug is classified as a pregnancy Category C drug. There are no adequate and well-controlled studies completed in pregnant women. Codeine should only be used during pregnancy if the potential benefit outweighs the potential risk of the drug to the fetus .

Codeine has shown embryolethal and fetotoxic effects in the hamster, rat as well as mouse models at about 2-4 times the maximum recommended human dose . Maternally toxic doses that were about 7 times the maximum recommended human dose of 360 mg/day, were associated with evidence of bone resorption and incomplete bone ossification. Codeine did not demonstrate evidence of embrytoxicity or fetotoxicity in the rabbit model at doses up to 2 times the maximum recommended human dose of 360 mg/day based on a body surface area comparison .

Nonteratogenic effects

Neonatal codeine withdrawal has been observed in infants born to addicted and non-addicted mothers who ingested codeine-containing medications in the days before delivery. Common symptoms of narcotic withdrawal include irritability, excessive crying, tremors, hyperreflexia, seizures, fever, vomiting, diarrhea, and poor feeding. These signs may be observed shortly following birth and may require specific treatment .

Codeine (30 mg/kg) given subcutaneously to pregnant rats during gestation and for 25 days after delivery increased the rate of neonatal mortality at birth. The dose given was 0.8 times the maximum recommended human dose of 360 mg/day .

The use in breastfeeding/nursing

Codeine is secreted into human milk. The maternal use of codeine can potentially lead to serious adverse reactions, including death, in nursing infants .

Precaution

It should be administered cautiously in asthma, uncontrolled blood pressure and pregnant women.It is specially important not to use aspirin during the last 3 months of pregnancy unless specifically directed to do so by a doctor because it may cause problems in unborn child or complication during delivery. It should be administered with caution to patients in nasal polyp and nasal allergy. Aspirin penetrates into breast milk. So, it should be administered with caution to lactating mothers.

Interaction

Salicylates may enhance the effect of anticoagulants, oral hypoglycaemic agents, phenytoin and sodium valporate. They inhibit the uricosuric effect of probenecid and may increase the toxicity of sulphonamides. They may also precipitate bronchospasm or induce attacks of asthma in susceptible subjects.

Volume of Distribution

This drug is distributed to body tissues shortly after administration. It is known to cross the placenta. The plasma contains high levels of salicylate, as well as tissues such as spinal, peritoneal and synovial fluids, saliva and milk. The kidney, liver, heart, and lungs are also found to be rich in salicylate concentration after dosing. Low concentrations of salicylate are usually low, and minimal concentrations are found in feces, bile, and sweat .

The volume of distribution of butalbital is reported to be approximately 0.8 L/kg. Butalbital is expected to distribute to most of the tissues in the body , including the mamillary glands and placenta. The plasma-to-blood concentration ratio was almost unity indicating that there is no preferential distribution of butalbital into either plasma or blood cells.

Caffeine has the ability to rapidly cross the blood-brain barrier. It is water and fat soluble and distributes throughout the body. Caffeine concentrations in the cerebrospinal fluid of preterm newborns are similar to the concentrations found in the plasma. The mean volume of distribution of caffeine in infants is 0.8-0.9 L/kg and 0.6 L/kg in the adult population.

Apparent volume of distribution: about 3-6 L/kg, showing an extensive distribution of the drug into tissues .

Elimination Route

Absorption is generally rapid and complete following oral administration but absorption may be variable depending on the route, dosage form, and other factors including but not limited to the rate of tablet dissolution, gastric contents, gastric emptying time, and gastric pH .

Detailed absorption information

When ingested orally, acetylsalicylic acid is rapidly absorbed in both the stomach and proximal small intestine. The non-ionized acetylsalicylic acid passes through the stomach lining by passive diffusion. Ideal absorption of salicylate in the stomach occurs in the pH range of 2.15 - 4.10. Intestinal absorption of acetylsalicylic acid occurs at a much faster rate. At least half of the ingested dose is hydrolyzed to salicylic acid in the first-hour post-ingestion by esterases found in the gastrointestinal tract. Peak plasma salicylate concentrations occur between 1-2 hours post-administration .

Butalbital gets readily and rapidly absorbed from the gastrointestinal tract. The time to reach the peak plasma concentrations is reported to be approximately 2 hours. Typical blood concentrations of butalbital peaked at 2.1 mg/L and declined to 1.5 mg/L at 24 hr. Plasma concentrations of 10 to 20 μg/mL have been associated with toxicity; coma and fatalities have occurred with concentrations of 25 to 30 μg/mL.

Caffeine is rapidly absorbed after oral or parenteral administration, reaching peak plasma concentration within 30 minutes to 2 hours after administration. After oral administration, onset of action takes place within 45 to 1 hour. Food may delay caffeine absorption. The peak plasma level for caffeine ranges from 6-10mg/L. The absolute bioavailability is unavailable in neonates, but reaches about 100% in adults.

Absorption

Codeine is absorbed from the gastrointestinal tract. The maximum plasma concentration occurs 60 minutes after administration .

Food Effects

When 60 mg codeine sulfate was given 30 minutes post-ingestion of a high high-calorie meal, there was no significant change in the absorption of codeine .

Steady-state concentration

The administration of 15 mg codeine sulfate every 4 hours for 5 days lead to steady-state concentrations of codeine, morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) within 48 hours .

Half Life

The half-life of ASA in the circulation ranges from 13 - 19 minutes. Blood concentrations drop rapidly after complete absorption. The half-life of the salicylate ranges between 3.5 and 4.5 hours .

The plasma half-life is about 35 hours. In a study of 5 healthy volunteers receiving 100 mg butalbital in combination with aspirin and caffeine, the mean plasma elimination half-life of butalbital was 61 hours, with the range of 35 to 88 hours.

In an average-sized adult or child above the age of 9, the half-life of caffeine is approximately 5 hours. Various characteristics and conditions can alter caffeine half-life. It can be reduced by up to 50% in smokers. Pregnant women show an increased half-life of 15 hours or higher, especially in the third trimester. The half-life in newborns is prolonged to about 8 hours at full-term and 100 hours in premature infants, likely due to reduced ability to metabolize it. Liver disease or drugs that inhibit CYP1A2 can increase caffeine half-life.

Plasma half-lives of codeine and its metabolites have been reported to be approximately 3 hours .

Clearance

The clearance rate of acetylsalicylic acid is extremely variable, depending on several factors . Dosage adjustments may be required in patients with renal impairment . The extended-release tablet should not be administered to patients with eGFR of less than 10 mL/min .

There is limited data on the clearance of butalbital.

The clearance of caffeine varies, but on average, is about 0.078 L/kg/h (1.3 mL/min/kg).

Renal clearance of codeine was 183 +/- 59 ml min-1 in a clinical study .

Renal impairment may decrease codeine clearance .

Elimination Route

Excretion of salicylates occurs mainly through the kidney, by the processes of glomerular filtration and tubular excretion, in the form of free salicylic acid, salicyluric acid, and, additionally, phenolic and acyl glucuronides .

Salicylate can be found in the urine soon after administration, however, the entire dose takes about 48 hours to be completely eliminated. The rate of salicylate is often variable, ranging from 10% to 85% in the urine, and heavily depends on urinary pH. Acidic urine generally aids in reabsorption of salicylate by the renal tubules, while alkaline urine increases excretion .

After the administration of a typical 325mg dose, the elimination of ASA is found to follow first order kinetics in a linear fashion. At high concentrations, the elimination half-life increases .

Butalbital predominantly undergoes renal elimination with 59 to 88% of the total dose administered being excreted from the kidneys as unchanged parent drug or metabolites. Urinary excretion products included parent drug (about 3.6% of the dose), 5-isobutyl-5-(2,3-dihydroxypropyl) barbituric acid (about 24% of the dose), 5-allyl-5(3-hydroxy-2-methyl-1-propyl) barbituric acid (about 4.8%), products with the barbituric acid ring hydrolyzed with excretion of urea (about 14% of the dose), as well as unidentified materials. Of the material excreted in the urine, 32% is conjugated. Elimination is not complete within 24 hours, and the drug accumulates with frequent administration.

The major metabolites of caffeine can be found excreted in the urine. About 0.5% to 2% of a caffeine dose is found excreted in urine, as it because it is heavily absorbed in the renal tubules.

About 90% of the total dose of codeine is excreted by the kidneys. Approximately 10% of the drug excreted by the kidneys is unchanged codeine .

The majority of the excretion products can be found in the urine within 6 hours of ingestion, and 40-60 % of the codeine is excreted free or conjugated, approximately 5 to 15 percent as free and conjugated morphine, and approximately 10-20% free and conjugated norcodeine .

Pregnancy & Breastfeeding use

Aspirin should be avoided during the last 3 months of pregnancy. As aspirin is excreted in breast milk, aspirin should not be taken by patients who are breast-feeding.

Contraindication

Aspirin is contraindicated to the children (Reye's syndrome) under 12 years, in breast-feeding and active peptic ulcer. It is also contraindicated in bleeding due to haemophilia and other ulceration. Hypersensitivity to aspirin, hypoprothrombinaemia is also contraindicated

Acute Overdose

Overdosage produces dizziness, tinnitus, sweating, nausea and vomiting, confusion and hyperventilation. Gross overdosage may lead to CNS depression with coma, cardiovascular collapse and respiratory depression. If overdosage is suspected, the patient should be kept under observation for at least 24 hours, as symptoms and salicylate blood levels may not become apparent for several hours. Treatment of overdosage consists of gastric lavage and forced alkaline diuresis. Haemodialysis may be necessary in severe cases.

Storage Condition

Store in a cool and dry place, protected from light.

Innovators Monograph

You find simplified version here Fiorinal w/Codeine


*** Taking medicines without doctor's advice can cause long-term problems.
Share