Sublingual administration

Nitroglycerin, the prototype of the nitrates is characterized by a rapid onset and short duration of action. It is usually administered sublingually (via the oro-mucosal route), which allows a rapid and efficient absorption and avoids the strong first pass effect after oral administration. Nitroglycerin is available as tablets, capsules (for sublingual administration) but also as transdermal preparations, sprays, and ointments. 

Nitroglycerin is a lipid-soluble substance that is rapidly absorbed across the sublingual or buccal mucosa. Its onset of action occurs within 2 to 5 minutes, with maximal effects observed at 3 to 10 minutes. Little residual activity remains 20 to 30 minutes after sublingual administration. The plasma half-life of nitroglycerin, given... 

Jones, T.E., Morris, R.G., Saccoia, N.C., Thorne, D. Dextromoramide pharmacokinetics following sublingual administration, Palliat. Med. 1996, 10, 313-317. 

Fig. 2. Plasma radioactivity profiles obtained in 2 healthy volunteers after administration of123I-Parj 1 by sublingual (a) or intranasal (b) route, respectively. 123I-Parj 1 was administered at time 0 for sublingual administration the subject swallowed at 30 min. The radioactivity is expressed as percent of the administered dose. 

As already observed for sublingual administration, even in this case both local retention and systemic absorption of allergen by intestinal tract are likely to occur, the locally retained fraction being higher. Notably the lack of bronchial deposition of radiolabelled Par j 1 seems to minimize the risk of asthma attacks due to undesired bronchial exposure, as previously discussed [5],... 

Feliziani Y Marfisi RM, Parmiani S Rush immunotherapy with sublingual administration of grass allergen extract. Allergol Immunopathol (Madr) 1993 21/5 173-178. 

It has sometimes been claimed that SLIT can lead to an increased risk in patients suffering from the oral allergy syndrome. The sublingual administration of pollen allergens which are cross-reacting with food allergens may in fact... 

A wide range of formulations have been developed and tested for buccal and sublingual administration. Various advances have been made over the years, which counteract the... 

The oral absorption of drugs has been recognized for many years, but the emphasis has been largely on sublingual administration. However, most of the potential benefits of this route apply... 

The pioneer drug, captopril, had a relatively short duration of action. Nonetheless, with sublingual administration it is used to elicit beneficial hemodynamic and clinical effects in hypertensive crises, acute myocardial ischemia, and acute CHF. Several long-acting analogue drugs are used nowadays as a first-choice therapy in cardiovascular diseases, and their minor differences have been summarized in this chapter. 

Disposition in the Body. Absorbed after parenteral or sublingual administration and metabolised mainly by A-dealkylation and conjugation. It is eliminated mainly in the faeces with a small proportion excreted in the urine, as metabolites. 

After sublingual administration of 0.3 mg to 1 subject, a blood concentration of about 0.001 ag/ml was attained in 3 minutes following an oral dose of 6.5 mg or application of an ointment containing 16 mg of glyceryl trinitrate to the same subject, peak blood concentrations of about... 

Following sublingual administration of 0.5 mg to 6 subjects, a mean peak plasma concentration of 0.0014 pg/ml was attained in 3 minutes after oral administration of 6.4 mg, a peak plasma concentration of 0.0026 pg/ ml was reported at 2 to 4 hours, and after topical administration of 35 mg, a mean peak plasma concentration of 0.0025 pg/ml was attained in 1 hour. Plasma nitrate and nitrite concentrations were undetectable after sublingual administration after oral administration peak plasma concentrations of about 0.5 pg/ml of nitrate and nitrite were attained in 5 and 2 hours respectively, and following topical administration, peak concentrations of about 0.7 pg/ml were reported at 5 hours and 1 hour respectively (A. Bashir et al., Br. J. din. Pharmac., 1982,14, 779-784). 

Half-life. Plasma half-life, after intravenous administration about 2 to 5 minutes after sublingual administration about 5 minutes. 

Disposition in the Body. Irregularly absorbed after oral or sublingual administration with extensive metabolism and conjugation occurring in the gut. Only about 10% of an inhaled dose reaches the lungs. Rapidly metabolised by 3-0-methylation and sulphate conjugation 3-0-methylisoprenaline exhibits weak activity. After intravenous administration, about 90% of a dose is excreted in the urine in 24 hours, mostly as the conjugated... 

The sublingual administration of methyltestosterone was examined by Alkalay et al. The sublingual tablet produced a 50%i higher relative bio availability when compared with the oral tablet or oral solution. The increased bioavailability was attributed to the avoidance of first-pass hepatic metabolism due to absorption from the sublingual vasculature and lymphatics. 

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