Propylene glycol adverse effects

Many of these reactions are related to the quantity of excipient found in a dosage form. Benzyl alcohol benzalkonium chloride, propylene glycol, lactose, and polysorbates are all associated with dose-related toxic reactions [52-54], Large-volume parenterals containing 1.5% benzyl alcohol as a preservative have caused metabolic acidosis, cardiovascular collapse, and death in low birth weight premature neonates and infants. The cumulative dose of benzyl alcohol ranged from 99 to 234 mg/kg per day in these patients [55,56], Dose-related adverse effects to excipients are of particular concern in the preterm, low birth weight infant because... 

Local adverse effects of topical minoxidil (usually in an alcohol-propylene glycol base) include dryness, irritation, pruritus, contact allergy (SEDA-11, 139), and photocontact allergy (SEDA-11,139). 

Many excipients have been associated with adverse reactions in those ingesting drugs and vitamin/mineral formulations containing these compoundsJ78 79 Antioxidants (e.g., sodium sulfite, sodium and potassium bisulfites, and metabisulfites), bacterial preservatives (e.g., benzyl alcohol and benzalkonium chloride), artificial sweeteners (e.g., aspartame and saccharine), coloring agents (e.g., FD C yellow 5, blue 2, and red 40), and propylene glycol. A few examples of the toxic effects of these follow. 

Propylene glycol is used as solvents in many formulations (e.g., oral, topical, and parenteral routes) for poorly soluble compounds such as phenobarbital, phenytoin, diazepam, and multivitamin concentrates. Because of the limited metabolic pathways in children younger than four years, number of adverse events has been described (laxative effects per os, contact dermatitis) but mainly serious systemic CNS depression. Seven of... 

The concentrations of licensed medications may be too high, necessitating further manipulation in the form of dilution with an excipient. However, when the concentration is low, the dose volume may be too large for some children. The excipients in many liquid formulations may not be suitable for selected patient groups. For example, the propylene glycol content in amprenavir liquid formulation makes it unsuitable for children under 4 years of age. Severe delayed-onset hypersensitivity reaction was associated with formulation of amoxicillin liquid the reaction may have been caused by the exicipent (Chopra et ai, 1989). Sweeteners, dyes and other excipients may cause adverse reactions and should be identified and restricted in paediatric formulations (Kumar et ai, 1996). Some clinical studies have been directed to ascertain the effect of drug concentration and frequency of... 

The most commonly used vehicle is water, for solutions as well as suspensions, emulsions and solubilisates. If a solution is required, co-solvents may be added (see Sect. 5.4.4) such as ethanol, glycerol 85 % and propylene glycol. Then-toxic and adverse effects should be fuUy considered. They are miscible with water and often have an antimicrobial effect as well. Lipophilic active substances may be brought into solution by a lipophilic solvent such as acetem. Another way of processing lipophilic solvents is to convert them into an emulsion. 

As a result of the above limitations, various approaches to raising the conductivity have been considered, such as the addition of plasticisers, e.g. organic liquids, propylene carbonate or ethylene carbonate or low molecular weight ethylene glycols. " However, the gain in conductivity is adversely associated with a loss of the mechanical properties and by a loss of the compatibility with the lithium electrode, both effects resulting in serious problems since they affect the battery cycle life and increase the safety hazard. 

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