Product Information
Registration Status: ActiveUNIDRYL CD EXPECTORANT is approved to be sold in Singapore with effective from 1989-05-22. It is marketed by EURO ASIA MEDICO PTE LTD, with the registration number of SIN02917P.
This product contains Ammonium Chloride 135mg/5ml,Codeine 5mg/5ml, and Diphenhydramine 14mg/5ml in the form of SYRUP. It is approved for ORAL use.
This product is manufactured by SUNWARD PHARMACEUTICAL PTE LTD in SINGAPORE.
It is a Pharmacy Only Medicine that can be obtained from a pharmacist at a retail pharmacy.
Description
Ammonium chloride is an inorganic compound with the formula NH4Cl and a white crystalline salt that is highly soluble in water. Solutions of ammonium chloride are mildly acidic.
Indication
1. Expectorant in cough syrups. 2. The ammonium ion (NH4+) in the body plays an important role in the maintenance of acid-base balance. The kidney uses ammonium (NH4+) in place of sodium (Na+) to combine with fixed anions in maintaining acid-base balance, especially as a homeostatic compensatory mechanism in metabolic acidosis. The therapeutic effects of Ammonium Chloride depend upon the ability of the kidney to utilize ammonia in the excretion of an excess of fixed anions and the conversion of ammonia to urea by the liver, thereby liberating hydrogen (H+) and chloride (Cl–) ions into the extracellular fluid. Ammonium Chloride Injection, USP, after dilution in isotonic sodium chloride injection, may be indicated in the treatment of patients with: (1) hypochloremic states and (2) metabolic alkalosis.
Mechanism of Action
1. Increases acidity by increasing the amount of hydrogen ion concentrations. 2. Ammonium chloride is used as an expectorant in cough medicine. Its expectorant action is caused by irritative action on the bronchial mucosa, which causes the production of excess respiratory tract fluid and make it easier to cough it up.
Pharmacokinetics
- Absorption
- Completely absorbed within 3–6 h. In healthy persons, absorption of ammonium chloride given by mouth was practically complete. Only 1 to 3% of the dose was recovered in the feces.
- Distribution
- Data not found.
- Metabolism
- Ammonium ion is converted to urea in the liver; chloride ion replaces bicarbonate.
- Elimination
Clearance
Data not found.
Toxicity
LD50 "Rat" after oral administration is: 1650 mg/kg. Overdosage of Ammonium Chloride has resulted in a serious degree of metabolic acidosis, disorientation, confusion and coma. If metabolic acidosis occur following overdosage, the administration of an alkalinizing solution such as sodium bicarbonate or sodium lactate will serve to correct the acidosis. Patients administering Ammonium chloride should be watched to the signs of ammonia toxicity including (pallor, sweating, irregular breathing, bradycardia, cardiac arrhythmias, local and general twitching, tonic convulsions and coma). It should be used with caution in patients with high total CO2 and buffer base secondary to primary respiratory acidosis. Intravenous administration should be slow to avoid local irritation and toxic effects.
Active Ingredient/Synonyms
Ammonium chloride | Ammonium chloride |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.
Description
An opioid analgesic related to morphine but with less potent analgesic properties and mild sedative effects. It also acts centrally to suppress cough.
Indication
For treatment and management of pain (systemic). It is also used as an antidiarrheal and as a cough suppressant.
Mechanism of Action
Opiate receptors are coupled with G-protein receptors and function as both positive and negative regulators of synaptic transmission via G-proteins that activate effector proteins. Binding of the opiate stimulates the exchange of GTP for GDP on the G-protein complex. As the effector system is adenylate cyclase and cAMP located at the inner surface of the plasma membrane, opioids decrease intracellular cAMP by inhibiting adenylate cyclase. Subsequently, the release of nociceptive neurotransmitters such as substance P, GABA, dopamine, acetylcholine and noradrenaline is inhibited. Opioids also inhibit the release of vasopressin, somatostatin, insulin and glucagon. Codeine's analgesic activity is, most likely, due to its conversion to morphine. Opioids close N-type voltage-operated calcium channels (OP2-receptor agonist) and open calcium-dependent inwardly rectifying potassium channels (OP3 and OP1 receptor agonist). This results in hyperpolarization and reduced neuronal excitability.
Pharmacokinetics
- Absorption
- Well absorbed following oral administration with a bioavailability of approximately 90%. Maximum plasma concentration occurs 60 minutes post-administration. Food does not effect the rate or extent of absorption of codeine.
- Distribution
- Apparent volume of distribution = 3-6 L/kg
- Metabolism
- Hepatic. Codeine is a prodrug, itself inactive, but demethylated to the active morphine by the liver enzyme CYP2D6 to morphine. 70-80% of the dose undergoes glucuronidation to form codeine-6-glucuronide. This process is mediated by UDP-glucuronosyltransferase UGT2B7 and UGT2B4. 5-10% of the dose undergoes O-demethylation to morphine and 10% undergoes N-demethylation to form norcodeine. CYP2D6 mediates the biotransformation to morphine. CYP3A4 is the enzyme that mediates the conversion to norcodiene. Morphine and norcodeine are further metabolized and undergo glucuronidation. The glucuronide metabolites of morphine are morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). Both morphine and morphine-6-glucuronide are active and have analgesic activity. Norcodiene and M3G do not have any analgesic properties.
- Elimination
Toxicity
Respiratory depression, sedation and miosis and common symptoms of overdose. Other symptoms include nausea, vomiting, skeletal muscle flaccidity, bradycardia, hypotension, and cool, clammy skin. Apnea and death may ensue.
Active Ingredient/Synonyms
(−)-Codeine | (5alpha,6alpha)-7,8-Didehydro-4,5-epoxy-3-methoxy-17-methylmorphinan-6-ol | (5α,6α)-7,8-didehydro-4,5-epoxy-3-methoxy-17-methylmorphinan-6-ol | 3-Methylmorphin | 3-methylmorphine | 7,8-didehydro-4,5alpha-epoxy-3-methoxy-17-methylmorphinan-6alpha-ol | 7,8-didehydro-4,5α-epoxy-3-methoxy-17-methylmorphinan-6α-ol | Codein | Codeína | Codéine | Codeine anhydrous | Codeine polistirex | Codeinum | L-Codeine | Methylmorphine | morphine 3-methyl ether | Morphine monomethyl ether | morphine monomethyl ether | morphine-3-methyl ether | O(3)-methylmorphine | Codeine |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.
Description
Dimenhydrinate, also known as Dramamine or Gravol, is an over-the-counter drug used to prevent nausea, vomiting, and dizziness caused by motion sickness. Dimenhydrinate is a combination drug composed of [DB01075] and [DB14132] in a salt form, with 53%-55.5% of diphenhydramine, and not less than 44%-47% of 8-chlorotheophylline, calculated on the dried basis. The antiemetic properties of dimenhydrinate are primarily thought to be produced by diphenhydramine's antagonism of H1 histamine receptors in the vestibular system [A1540] while the excitatory effects are thought to be produced by 8-chlorotheophylline's adenosine receptor blockade [A33889]. The addition of 8-chlorotheophylline was initially intended to counteract the sedative effects of diphenhydramine. When used in large doses, dimenhydrinate has been shown to cause a "high" characterized by hallucinations, excitement, incoordination, and disorientation [A1539].
Indication
Dimenhydrinate is indicated for the prevention and treatment of nausea, vomiting, or vertigo of motion sickness.
Mechanism of Action
The mechanism by which some antihistamines exert their antiemetic, anti-motion sickness, and anti-vertigo effects is not precisely known but may be related to their central anticholinergic actions. They diminish vestibular stimulation and depress labyrinthine function. An action on the medullary chemoreceptive trigger zone may also be involved in the antiemetic effect. Dimenhydrinate is a competitive antagonist at the histamine H1 receptor, which is widely distributed in the human brain. Dimenhydrinate's anti-emetic effect is probably due to H1 antagonism in the vestibular system in the brain.
Pharmacokinetics
- Absorption
- Well absorbed after oral administration.
- Distribution
- Metabolism
- Hepatic (cytochrome P-450 system).
- Elimination
Toxicity
Symptoms of overdose include delerium, hallucinations, and excitment. Patients may be violent and confused.
Active Ingredient/Synonyms
(O-Benzhydryl(dimethylamino)ethanol) 8-chlorotheophyllinate | 8-chloro-1,3-Dimethyl-3,7-dihydro-1H-purine-2,6-dione - 2-(diphenylmethoxy)-N,N-dimethylethanamine (1:1) | Benzhydryl-beta-dimethylaminoethylether 8-chlorotheophylline | beta-Dimethylaminoethyl benzhydryl ether 1,3-dimethyl-8-chloroxanthine | Dimenhidrinato | Dimenhydrinatum | Diphenhydramine 8-chlorotheophyllinate | Diphenhydramine 8-chlorotheophylline | Diphenhydramine theoclate | Diphenhydrinate | N,N-Dimethyl-2-diphenylmethoxyethylamine 8-chlorotheophyllinate | O-Benzhydryldimethylaminoethanol 8-chlorotheophyllinate | Dimenhydrinate |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.