To go further, even the instruction “by the mouth” is ambiguous and could mean orally, buccally, or sublingually. Those all have different absorptions with the latter two being mucous membranes and therefore bypassing the liver, leading to different (generally better) bioavailability of medications dependent on the health of those tissues and the type of medication.
You know for a fact that instruction is there because someone tried the other options
Are there tablets for the other options?
Suppositories for rectal use. Powdered for nasal use.
Don’t know about urethral, vaginal, or ear canal.
To go further, even the instruction “by the mouth” is ambiguous and could mean orally, buccally, or sublingually. Those all have different absorptions with the latter two being mucous membranes and therefore bypassing the liver, leading to different (generally better) bioavailability of medications dependent on the health of those tissues and the type of medication.
No idea why you got downvoted. They arent rare, Zofran the most common anti nausea med is meant for sublingual.
For vaginal use, there are ovules, like clindamycin.
Yes