A sublingual tablet is usually a flat tablet that is small enough to fit under your tongue, according to Drugs.com. The active ingredient of the sublingual tablet is typically absorbed directly by the saliva and the tablet dissolves very rapidly. You can take certain medications and vitamins sublingually.
Not all medications are available in the form of a sublingual tablet. When sublingual tablets are dissolved under your tongue, the medication directly enters your bloodstream via capillaries that are under your tongue. This process takes only a few minutes. Normally, when you swallow a medication, your body has to digest the medication before it enters your bloodstream; this can take hours.
Not all drugs can be administered sublingually, but those that can include some steroids, barbiturates and certain vitamins and minerals. Certain cardiovascular drugs, such as nitroglycerin, are also available in sublingual tablets. Vitamin B-12 is often taken under the tongue. You do not need a prescription to purchase sublingual vitamins and minerals, but other sublingual medications do require a prescription just like other drugs.
Since sublingual tablets dissolve quickly and the medication enters the bloodstream right away, medications can work faster than if they were taken orally, swallowed and digested. This means you don’t have to wait for the medication to do its job, which is especially good for those who take heart medications and need them to work quickly. Since sublingual tablets are dissolved, they are not broken down and altered as traditional medications and vitamins are when they pass through the gastrointestinal tract.
Due to the fast rate at which sublingual tablets dissolve and enter the bloodstream, it can be life-threatening if you were to overdose when taking a prescribed medication. Overdosing on a drug such as sublingual nitroglycerin can result in syncope, tachycardia, bradycardia, hypotension, vertigo, convulsions, paralysis and coma. If your health care provider prescribes or recommends any drugs or supplements to be taken sublingually, use extra caution to ensure that you do not overdose. If you think you may have accidentally taken too much, call for emergency medical help.